A Contemporary Study of Schools in Havana and the Role of Physical Education in Castro’s Cuba

By Julia Wilkins and Robert J. Gamble, Ph.D.
Abstract

This article examines Cuban education in a historical perspective and how governments in power have altered the system of instruction on the island. The authors discuss the increased emphasis on physical education under Castro’s rule and report findings from their observations in five Cuban schools.  The article concludes with explanations and a rationale for the central role of physical fitness in the everyday lives of Cubans.

Introduction

Cuba is the only Communist country in the Western Hemisphere and one of the last in the world.   Its system of government is defined in its Constitution as “a socialist state of workers and peasants, and all other manual and intellectual workers.”  The belief that workers should
run the government, private property should be prohibited, and wealth should be distributed equally are all part of the Communist ideology.  The role of the state is to provide work, education, medical care, food, clothing and housing for all citizens. 

After the Communist Revolution in1959, the emphasis in schools was to socialize children to be good Communists who would support the new Castro regime. Under this new education system, physical education, fitness, and health became top priorities. Castro, who initiated these changes, was himself an exceptional athlete, who at one time was considered for professional trials by two American basketball teams and came close to representing Cuba at Olympic-level discus throwing (Sheehan, 1995).  Under his new regime, special schools for students with athletic talent were set up and facilities for a variety of sports were established.

The two most popular competitive sports boys train for are boxing and baseball, for which Cuba has gained an international reputation.  National teams regularly take first place in the Central American and Caribbean Games and Cubans have also repeatedly won gold, silver, and bronze medals.  The women’s volleyball team is the best in the world and has won three straight Olympic gold medals.  Their international standing in athletics is a great source of national pride for Cubans. Most sports in Cuba, however, are played on an amateur basis and top athletes do not enjoy the financial rewards of success known to professional athletes in the U.S. Castro’s support of athletics is evident throughout the island.  In the words of Roberto Herrera, Vice President of the Cuban Olympic Committee, “It’s the system of Cuba, the support that the state gives to sport, that has made these results possible.”  Since Castro came to power, an accentuation on physical exercise has become an integral part of the daily curriculum in schools at all grade levels and also permeates the day-to-day life of the wider society.

Cuban Education in a Historical Perspective

Cuba was first colonized by Spain in 1511 when the Spanish came to Cuba in search of gold.  Early Spanish rule was marked by several Cuban revolts for independence.  The first revolt to incorporate education into its aims was led by Jose Marti in 1895.  He argued that, “to be educated is the only way to be free” (Morrison, 1999).  His rallying call was “Cuba Libre”.  Cuba Libre, it was argued, could not be established without the foundation of a system of free, universal, secular public education (Johnston, 1995).

The United States remained officially neutral during these revolts,
even though it was secretly negotiating with Spain to purchase Cuba.  Its position regarding Spain changed, however, after the explosion of the battleship U.S.S. Maine in 1898.  The U.S. blamed Spain for the alleged attack and declared war.  With American troops as well as nationalist rebels fighting against the loyalist troops, the war against Spain ended in a few months.  In December 1898, under the Treaty of Paris, Spain relinquished its claim to Cuba and an American military government was set up to govern the island.  For the next three years the U.S. army was primarily engaged in reconstructing the infrastructure of the island.  The U.S. Government sponsored public works programs including the building of schools and roads (Sheehan, 1995). 

For many Cubans, however, U.S. rule was not a desirable alternative to Spanish rule.  Although the U.S. had established a public education system, this was perceived as a vehicle to “Americanize” Cuban culture.  This objection was not without foundation--the United States was educating Cuban school-children using Ohio’s state curriculum as the basis for the new Cuban curriculum, Cuban teachers were sent to the U.S. for training, U.S. educators began teaching in Cuba, and Spanish translations of U.S. textbooks were adopted in all schools (Johnston, 1995).

By the 1920s, it became apparent that the American-run education system was failing.  In addition to small numbers of children completing primary education, schools were unevenly distributed and faced low enrollment, low attendance, shortages of resources, and poor hygiene.  Cubans’ awareness of these problems spurred a significant resurgence of nationalist sentiment.  Nationalists believed that for the ideals of Cuba Libre to be met, the development of a unique Cuban consciousness, committed to collective progress, was necessary.  They demanded a system of education that was inspired by “love of patria”, and actively focused on Cuba, its history, its heroes, and its struggle for independence (Johnston, 1995).

Cuba Under Batista’s Rule

         In 1933, the President of Cuba, Gerardo Machado, was deposed by an army coup, and the following year Fulgencio Batista emerged with American support as Cuba's dictator.  Although the Constitution only permitted a president to serve one term in office, in 1952 Batista staged a second coup and ruled as Cuba's dictator for six more years before being deposed himself by Fidel Castro. Under Batista’s rule, Cuba’s economy thrived.  The United States and other foreign companies set up businesses in Cuba and enjoyed record profits. While the government got richer however, the people of Cuba got progressively poorer.  Little money went into public works or education and large-scale corruption permeated every aspect of political and social life.  Havana became a haven for the seamier side of life; casinos, bars, and brothels flourished.  The tourists who kept these establishments in business were oblivious to the poverty underpinning the private wealth of a minority of politicians and their close supporters.  In the rural areas
especially, many families could barely feed themselves and malnourishment became widespread (Sheehan, 1995).  Health and education of the common people were clearly not priorities of Batista’s government.

Castro’s Revolution

         Fidel Castro intended to contest the 1952 elections, but when they failed to take place, he adopted more direct action to overthrow the Batista dictatorship.  Together with the Argentinian revolutionary Che Guevara, he waged a successful guerilla campaign, which gained the support of ordinary Cubans, including homemakers, students, and even professional
groups who shared their vision of freedom (Sheehan, 1995).  Batista was deserted by his army after years of guerilla warfare, and fled Cuba on January 1, 1959.  The rebel army marched into Havana a week later.  The corruption and inequality that characterized Batista's Cuba had long been known and the downfall of Batista's government was therefore hailed as a triumphant victory both in Cuba and around the world.  The new socialist society envisioned by Castro, however, destroyed relations between Cuba and the United States and by January 1961 diplomatic relations between the two countries were formally broken off.  The Cuban government closed down American-owned casinos, and took control of U.S. sugar estates, cattle ranches, oil refineries, and other industries.  In response, the United States government imposed a trade embargo against Cuba, restricting the amount of food and other products shipped to the island.  The Cuban government then seized all remaining U.S. assets.  Castro’s closest ally, the Soviet Union, provided much-needed military and economic support.  As Russian trade and assistance grew, the United States became increasingly concerned with Castro’s communist leanings. In addition, Cuba's willingness to actively support Communist movements
in Central and South America and Africa was seen as a threat to American interests and exacerbated an already frigid relationship.

Cuba's recent history continues to be dominated by hostility between the two countries. Even though Cuba has ceased to represent a real threat to the United States since the breakup of the Soviet Union, the ban on trade with Cuba remains, and the loss of Russian aid estimated at $3 million a day, has caused its economy to plummet.  The United States tightened its trade embargo in 1996 by passing the Helms-Burton Act, which allows sanctions to be placed on countries trading with or investing in Cuba.  As a result, Cuba has experienced food shortages and lack of other essential staples.  The economic hardships faced by the country are apparent across the island--in schools, stores, hospitals, housing, recreational facilities, and general amenities.

Education Under Castro

In 1958 there were almost 1 million illiterate people in Cuba, and over two-thirds of the rural population had no schools.  After the Revolution, Castro closed all schools for eight months and sent 250,000 students and teachers into rural areas to teach reading and writing skills.  By 1962, the illiteracy rate dropped from 24 percent to 4 percent.  Old military headquarters, business offices, and police stations were converted into schools and with financial assistance from the Soviet Union; thousands of volunteers built new ones. Today, education is universal for everyone from kindergarten to university, and the 95 percent literacy level is among the highest in developing countries.  Cuba also has one of the lowest teacher-student ratios in the world; about 1 to 39 as compared to 1 to 77 in the United States (Morrison, 1999).

Cuban children go to primary school from age 5 to 11 or 12, and to secondary school until they are 17.  There are a variety of schools students can attend, although all are state-run.  Besides the special schools for athletic students, those with artistic talent can attend vocational arts schools where music, ballet, modern dance, and visual arts are combined with conventional studies.  There are also special facilities in many schools that provide enrichment for children with learning disabilities, as well as separate schools for children with severe disabilities.  There are no private, church, or home schools, however, and thus no curricula alternatives.  All Cuban youth are therefore exposed to the same ideology.  The Ministry of Education not only develops and disseminates the national curriculum; it coordinates the printing of textbooks and materials that are used in all schools (Vista & Lindahl, 1999).

In addition to free education, the government provides free medical care for all citizens.  After the Revolution, Cuba gained a worldwide reputation for the high quality and standards of its health service.  There is now one doctor for every 270 residents, a lower ratio than the United States, and the infant mortality rate is one of the lowest in the world (Morrison, 1999).  However, in the past decade, conditions in hospitals have declined and medicine and equipment have become dangerously scarce.  Despite the lack of supplies, the emphasis on health and wellness has remained an integral component of the Cuban education system.  To monitor the health of children, most schools have an in-house physician in addition to a school nurse.  Students diagnosed with medical or dental needs are referred to public health services.  Food subsidies are also given to each school to ensure that children are well nourished.  All schools receive regular supplies of dried milk, sugar, rice and beans, allowing children to eat two meals at school daily.

The education system is a key element in maintaining Cuba’s communist state.  The aim of post-revolutionary Cuban education has been to teach the rights and duties of citizenship, to foster patriotism and national solidarity, and to meet the country’s employment and production requirements.  Toward this end, it is necessary for the state to ensure that its citizens are physically fit and in good health.  It is clear that this priority takes root in the school-system at the pre-K level. 

Motor Skill Development in Schools

General Observations

            This section is based on observations and interviews conducted in five schools in and around Havana in December 2000.  The authors spent two days at the Ograrito Infant and Primary School in Old Havana, a pre-K and elementary school housed in the same building, one day at Guerrillero
School of America
, an elementary school also in Old Havana, and the fourth day at Jose Martinez School near the Capitol building in Central Havana.  On the fifth day we visited the Domingo Martinez Primary School located in Guanabo, a town on the coast, about 30 miles east of Havana.     

Most of the schools we saw were built for another purpose and have undergone renovation since Castro’s take over.  Before the Revolution, the Ograrito Infant and Primary School and the Jose Martinez School were business offices and the Guerrillero School of America was a police station.  Only the Domingo Martinez Primary School in Guanabo was built as a school in the 1960’s with Soviet financing.  This school building was constructed in rectangular fashion around a large open patio, similar to other schools built during that period throughout the Caribbean.

Noticeable in all the schools we visited was the severe lack of supplies.  In two of the schools, textbooks were kept in the principal’s office and were shared by classes.  We witnessed four children sharing one book and even saw students sharing pencils.  Technology was
virtually non-existent.  Manual typewriters were used in the offices of all the schools we visited.  The Ograrito Primary School had one television and VCR that were donated from a Canadian-based charitable organization and they were kept in a cage.  We were told they got little use because of the small number of video tapes available, combined with the fact that Cuban television programs do not begin broadcasting until after school hours. Administrators expressed hope that they would be able to use this form of media as an educational tool in the future.  All of the buildings were in disrepair, with crumbling walls in dire need of repainting, and archaic plumbing and lighting systems.  What was apparent in all the schools however, was the cleanliness, high standards of hygiene in the cooking and eating areas, and attempts to brighten rooms despite the lack of resources and materials.

Patriotism abounded in the halls and classrooms and was evident in all visual displays--bulletin boards, learning centers, art forms, and presentations of student work.  Pictures of Che Guevara and Bolivar, heroes endorsed by Castro, were exhibited liberally throughout the buildings.  The themes of “love for country”, citizenship and loyalty were demonstrated in both the students’ hands-on activities and written assignments.

In line with the communist ideal of eliminating class distinctions, all students wear compulsory school uniforms.  In secondary schools, the most common attire is a white shirt for all, with khaki pants for boys, and a blue or khaki skirt for girls.  Many secondary schools also require boys to wear the socialist “pioneer” bandana.  The most common uniform for elementary children is a white shirt with maroon pants, shorts or skirts, and the socialist “pioneer” bandanas. 

Five Visits to Schools in and around Havana
 
        Our first field site visitation took place at Ograrito Infant and Primary School.  The school, which serves students from pre-K through sixth grade, is situated in Old Havana on a busy commercial street. The elementary school is located on the ground level and the pre-school is housed on the second floor. We were allowed to talk to teachers and interact freely with children.  In the elementary classes, the emphasis on motor development was apparent throughout the activities we observed.  The children were engaged in manipulative, fine motor as well as gross motor activities.  In small groups they used colorful plastic blocks and shapes while teachers moved throughout the room encouraging and assisting them.  Although, as in all Cuban schools, the resources were very limited, teachers made the most of materials that were available by creating their own colorful, manipulative objects to enhance students' learning. 

Excluding the variable of aesthetics, the learning environment at the Ograrito Infant and Primary School resembled that of a Montessori program.  There were different stations throughout the classroom presenting various activities for the young children.  The teachers monitored and assisted free movement from one activity to another.  The building administrator told us that during daily recess time, which was staggered throughout the classrooms, teachers escorted children to a nearby playground where they participated in exercises and team sports.

The principal of the preschool upstairs did not speak English, so we
communicated through the elementary building administrator who
accompanied us.  Activities in the pre-K rooms were typical of American
schools.  In the class we observed, there was a slide, a block area, a
rest area and a housekeeping corner.  When we arrived, the young children
were sitting at tables listening to the teacher.  The interpreter said the
topic was, “patriotism and love for Cuba”. 

The children transitioned from this lesson to a semi-structured activity
in which they moved freely around the room interacting in the various “centers”. The building administrator told us that “working with the hands is very important--we also like them to run and skip”.   The teacher seemed to encourage this “free” play, only becoming involved for management and discipline issues.  During this time the teacher set the tables for lunch, which consisted of the country’s staples--rice and beans.  Each child had his or her own cup, which they were not allowed to share.  After lunch the children rested on cots in the back of the room while the teacher cleaned the tables.  After a half hour rest, during which several children slept, they were taken outside for a walk.  Because the school was located in a congested urban area, we were told the preschoolers did not walk to the playground where the elementary children performed their daily physical exercises.

Guerrillero School of America, our second school for observation, was located about six blocks from the Capitol.  After interviewing the principal, we were escorted to a class of seventh graders, arriving at the end of a history lesson’s oral presentations.  We then accompanied the class to a local parkway, a ten-minute walk from the school.  With little direction on arrival, the children began a routine that consisted of a five-minute regimen of stretching exercises.  They were then divided students into two teams for several running and ball games and upon their enthusiastic request we participated in a type of relay tag.  The teacher, who spoke broken English, told us this activity was part of the daily program.

We also observed a group of 8 and 9 year olds from another school involved in similar activities farther down the parkway, using the paved area for recess and physical education.  After these children stretched, they formed a large circle and played a teacher-supervised
variation of “Duck Duck Goose”.   This took place as pedestrians weaved around them and traffic traveled the busy street.  After 45 minutes, we returned with the students from Guerrillero School for the staple lunch of rice and beans, which they ate in their classroom. 

The following day we took a field trip with 14 and 15 year olds from Jose Martin School, also near the Capitol building.  Upon entering the school, which was a former administrative building, we were greeted by the principal who escorted us to a class that was going to the Havana National Museum.  We accompanied them on their walk to the museum, which were several blocks away.  The students, some of whom had fathers and other family members living in the States, were very curious about American culture and asked questions about life in the States throughout the entire walk.

At the Havana National Museum, the students wandered from room to room and appeared more interested in conversation than in the exhibits, which seemed typical of adolescents of that age.  A few, however, did take notes and asked the museum guides questions.  The museum was open air with a large statue of Christopher Columbus at the entrance.  The guides attempted to communicate with us, but spoke very little English so most of our dialogue took place through facial and hand gestures.  We stayed in the museum until lunchtime and then returned to the school.

After lunch, which was rice with vegetables and chicken gravy, the students had one academic class before their physical education.  Across from the Jose Martin School was a small park where the students participated in gender-segregated motor activities.  The girls performed a dance routine with a female teacher and the boys played a variation of kick ball with a male teacher.  Students were dismissed for the day directly from the park and many followed us as we walked to our bus stop.  It was apparent they were immensely curious about the United States, particularly those children with relatives who had defected here.

Our last observation was at an elementary school in Guanabo, a small
town about 30 miles east of Havana on the northern coast.  The Domingo
Martinez Primary School
was in an ideal location for outdoor activity.  The back of the building was on the beach while the front faced a beautiful park.  Also within walking distance was a well-maintained playing field, which children in the older grades used for stretching exercises, running, and soccer games.

The building was designed in rectangular formation with greenery and a small playground in the middle.  There was no electricity in the classrooms and the windows had slats, rather than glass.  While rooms on one side of the building were shaded and dark, the rooms on the other side received direct sunlight and were bright and very hot.  At this school there was clearly a paucity of materials but this did not dampen the mood of students or teachers who were lively, hospitable and in good spirits.

According to the building principal, children had physical education
in the park and adjoining field for at least one hour daily.  Older students walked to the nearby playing field for stretching exercises and team games, a perfect location for such activities because of the serene setting and ocean breeze.  In addition, other activities such as dance, dodge ball, and netball were observed as part of the physical education program.  These were played in the adjacent park under the direction of a teacher.  Before returning to school, children had 20 minutes of unstructured play during which time they were allowed to purchase candy from a nearby vendor.  The most fascinating event we witnessed at this school occurred at dismissal when a donkey-driven cart picked up a large group of children to take them home.  They literally hung from the cart laughing and singing songs as the donkey was led down a paved road.

It was noted in all the schools we observed that supervision was a high
priority.  Classroom teachers led stretching exercises, dance classes, running activities, and a variety of team games.  When asked, teachers maintained that physical education consumed much of their time during the day.  They expressed full support of these endeavors and their involvement in them.

Reasons for the Emphasis on Physical Education

It is clear that Cubans’ love of physical activity permeates every aspect of the culture irrespective of the limited resources available.  Despite the lack of gymnasiums in schools and outdoor sports facilities, educators use the natural environment and favorable weather conditions to their advantage.  It was commonplace to see students walking to local parks for exercise and games during the school day. 

The central role that fitness plays in children’s school day is inseparable from their daily routines.  Children of all ages were seen playing ball games such as “stickball” on the streets and in parking lots throughout Havana after school hours.  Girls were commonly seen doing dance routines, playing hopscotch, and skipping in the streets. There were basketball nets in numerous vacant lots and the sport seemed as popular among youth as their national sport, baseball.  Soccer was played primarily in the countryside, which could be attributed to space limitations in the city.  Although the only tennis courts we observed were located on hotel grounds (which are only available to tourists), many people, adults and children alike, hit balls with rackets against walls and sides of buildings.  In addition, a popular mode of transportation among school-age boys was a homemade scooter fashioned out of wooden planks on two sets of wheels with an attached fruit crate and handles.  Groups of youngsters were seen skillfully maneuvering throughout the streets of Havana on these contraptions.

It is clear that wellness and physical fitness are highly valued in Cuban culture.  Cuban children appeared energetic and healthy and obesity was virtually non-existent.  This can be attributed a number of factors, including the priority on school physical education programs, the low fat diet (the staples are primarily carbohydrates), the lack of meat, and the scarcity of “junk food”.   Despite the fact that cigar manufacturing is one of the primary industries in Cuba, we did not see teenagers smoking cigars or cigarettes.  In addition to being financially prohibitive, tobacco consumption among youth is probably minimal due to the island-wide value placed on good health.

So what are the underlying reasons for the focus on health and physical fitness in Cuban society?  One might be necessity.  With the dearth of materials in schools - the lack of technology, textbooks, and basic supplies such as paper and pencils - physical education seems a viable alternative to classroom-based instruction. Stretching, dancing, and running do not require materials and most ball games can be played with just one ball.  Weather conditions are also conducive to an active outdoors lifestyle and is something all Cubans take advantage of, whether involved in work or recreational activities.

It can also be seen that the emphasis on physical fitness and sports serves
Castro’s regime on many different levels.  It provides for a healthy workforce, a physically fit military, and the group mentality needed for acceptance of a Communist state.  No secret is made of the fact that the overriding aim of the Cuban education system is to produce good Communists who will share the state’s ideals.  As U.S. children begin their school day with the pledge of allegiance, Cuban’s begin theirs with the slogan, “Pioneers of communism, we shall be like Che” (Morrison, 1999).  Article 62 of the Cuban Constitution states, “that no rights granted by this Constitution can be exercised against the existence of and objectives of the Communist state.”  In addition, Article 8 of The Code of the Child and of Youth (1978) requires that “Society and the State work for the efficient protection of youth against all influences contrary to their Communist formation”.  An integral part of the Communist ideology, central to young people’s  “Communist formation,” is the belief that manual labor is productive and equal to other forms of work.  To this end, in 1970, the Cuban government created The School in the Country where students divide their time between the classroom and the fields.  The aim is to make students aware of their social responsibilities and reduce prejudice to manual labor (Morrison, 1999). 

Children in Cuba are taught at a young age that they must contribute to building and sustaining the country through physical work.  Starting in elementary school, students are responsible for cleaning and maintaining the school building and grounds.  In addition, from seventh through twelfth grade, students are required to spend 30 days each year working on the land.  Eighty-percent of Cuba’s total land area is farmland and agricultural work is therefore essential to the economy.  This manual labor also serves to instill the “work ethic” through which children come to realize that all citizens must participate equally in supporting the island's economic system.
 
         In order to have a workforce that will work together for the good of
society, it is also necessary to have a compliant population capable of working cooperatively.  The emphasis on team sports throughout the education system provides foundational skills needed to work cooperatively rather than competitively in the workforce.  In the post-revolution years, the government actively promoted team-oriented work programs by establishing microbrigades--small groups of workers who took time off from their regular occupations to participate in building programs, the workers being a mixture of professional and manual workers of both sexes.  In urban areas, microbrigades were used for public housing programs, and in the countryside they were used to build new schools or homes for the elderly.  These building programs have been brought to a standstill in recent years however, due to a lack of raw materials resulting from the current economic crisis (Sheehan, 1995).

In order for the government to gain maximum productivity from its workers, it is also imperative they be kept in optimal health.  Since the U.S. trade embargo, Cuba has experienced an acute shortage of medicine and medical equipment.  It is therefore in the state’s best interests to ensure minimal usage of medical services.  Attempts to minimize health care consumption may underlie the government requirement of monthly health check-ups for all citizens.  This pro-active measure aims to be more cost-effective than providing medicine and hospitalization for the sick.  Monitoring the health of all citizens on a routine basis also defers the onset of age-related illnesses and care.  As can be seen from the United States’ health system, long-term care facilities are a major financial drain on the medical community.  These costs are kept to a minimum in Cuba, partially offset by national fitness programs for seniors.  In addition to these monthly check-ups and fitness programs, the government also attempts to keep all citizens in good health by ensuring that dietary needs are met through rations of daily bread and other staples such as beans and rice. 

Another reason Cuba needs a fit; athletic population is because of the importance of the military, which has one of the largest armies in Latin America (Morrison, 1999).  Cuban men between sixteen and fifty years old are drafted into the army for two years unless they choose to work on the land.  The army, which includes large numbers of women, also performs many non-military agricultural jobs such as sugarcane harvesting and farm work.  To function in either a military or a civilian capacity, it is imperative that the population be in optimal health.

Conclusion

It is apparent that since Castro’s take over, education in Cuba has improved dramatically. Despite the austere conditions and severe lack of materials, universal education on the island has drastically reduced illiteracy and has provided for individual needs throughout the island.   

Based on our research and observations, it is evident that physical education is fundamental to the Cuban way of life. At all levels of Cuban society, starting in early childhood education and progressing through adulthood, Cubans are immersed in physical activities. There are several factors that contribute to this phenomenon, including government programs designed to promote a healthy, active population; emphasis in the school curriculum; a proud history of competitive sports; and favorable weather conditions.  It is a result of these interconnected influences that physical activity has come to play the integral and pivotal role it does in Cuban culture.  The Cuban message is overtly reinforced in these words displayed across the main throughway of Havana, “Take Care of Your Health.  Practice Sports.”

References

Herrera Roberto in Cuban sports (2001, Week 15).  Only a Game [On-line serial].  Available: www.onlyagame.org/onlinefeatures/cuba1.shtml

Johnston, L. (1995).  Education and Cuba Libre, 1898-1958.  History Today, August 1995, v 45, n8, p.26-7.

Morrison, M. (1999).  Cuba.  Children’s Press: New York, NY.

Sheehan, S. (1995).  Cultures of the World: Cuba. Marshall Cavendish
Corporation: North Bellmore, NY.

Vista, C. & Lindahl, R. A. (1999).  Comparing the Challenges Facing Education.  Education, Fall 1999, v 120, n1, p. 45-52.