History 261 History and criticism 102 Politics and government 70 Social conditions 49 English literature 35 Criticism and interpretation 30 Mathematical models 26 Mathematics 26 Social aspects 26 Fishing - methods, gear, equipments, apparatus, materials 23 Foreign relations 23 Women 23 Economic conditions 22 Philosophy 22 Agricultural engineering 21 Intellectual life 21 Agroecological requirements 20 Law and legislation 20 Agriculture 19 Equipment and supplies 19 Nutrition 18 Data processing 17 Church history 16 Research 16 Biotechnology 15 Computer networks 15 Image processing 15 Nutrient requirements 15 World War, 1939-1945 15 Agronomy 14