No Subject field
 00 GENERAL CONCEPTS.
 01 PHILOSOPHY. ETHICS. SEMIOTICS.
 02 RELIGION. THEOLOGY. ESOTERICISM.
 03 SCIENCE AND TECHNOLOGY.
 04 EDUCATION. PEDAGOGY.
 06 PSYCHOLOGY.
 07 SOCIOLOGY. SOCIAL PSYCHOLOGY.
 08 EMPLOYMENT. WORKING CONDITIONS. OCCUPATIONS.
 10 POLITOLOGY. POLITICS.
 11 GOVERNMENT. ADMINISTRATION. CIVIL DEFENCE. SECURITY SERVICE.
 12 SOCIAL POLICY.
 13 LAW. LEGISLATION.
 15 MILITARY AFFAIRS. ARMAMENT. MILITARY EQUIPMENT.
 17 DEMOGRAPHY. STATISTICS.
 18 JOURNALISM. COMMUNICATION. MEDIA. ADVERTISING.
 19 NATURE PROTECTION. ENVIRONMENT PROTECTION. ENVIRONMENT TECHY.
 20 GEOLOGY. HYDROLOGY. CLIMATOLOGY.
 21 MATHEMATICS.
 22 ASTRONOMY. ASTROPHYSICS. SPACE EXPLORATION.
 23 PHYSICS.
 24 CHEMISTRY. CHEMICAL INDUSTRY.
 25 BIOLOGY. MICROBIOLOGY. GENETICS. ANTHROPOLOGY.
 26 BOTANY.
 27 ZOOLOGY.
 28 MEDICINE. BIOCHEMISTRY. ANATOMY. PHYSIOLOGY. COSMETICS.
 29 ECONOMY. ECONOMICS. FINANCE. TRADE.
 30 AGRICULTURE. HORTICULTURE. ANIMAL BREEDING. VETERINARY.
 31 FORESTRY. HUNTING. FISHERY. FOREST AND WOODWORK INDUSTRY. PULP AND PAPER INDUSTRY.
 34 CATERING. DOMESTIC ECONOMY.
 35 ELECTRICAL TECHNOLOGY. ELECTRONICS. ENERGETICS.
 36 INFORMATICS. INFORMATION TECHNOLOGY. AUTOMATICS.
 39 MECHANICAL ENGINEERING. METAL INDUSTRY. METALLURGY. MINING.
 43 LIGHT INDUSTRY. TEXTILE INDUSTRY. LEATHER INDUSTRY.
 44 BUILDING. CONSTRUCTION. SANITARY ENGINEERING.
 45 TRAFFIC. TRANSPORT. COMMUNICATION.
 47 ART. ARCHITECTURE.
 48 PHOTOGRAPHY. CINEMA.
 49 MUSIC.
 50 THEATRE. DANCE.
 51 SPORTS. PHYSICAL CULTURE.
 52 HOBBIES. LEISURE ACTIVITIES.
 53 INFORMATION SCIENCE. LIBRARIANSHIP. MEMORY INSTITUTIONS. PUBLISHING. TYPOGRAPHY.
 54 LINGUISTICS. LANGUAGES.
 55 LITERARY SCIENCE. LITERATURE. FOLKLORE.
 56 HISTORY. ARCHAEOLOGY.
 58 ETHNOLOGY. CULTURAL ANTHROPOLOGY.
 59 GEOGRAPHY. GEODESY. CARTOGRAPHY.
 60 GEOGRAPHICAL NAMES.