Classification
000 - Computer science, information & general works
13
001 - Knowledge
1
003 - Systems
1
004 - Data processing & computer science
2
005 - Computer programming, programs & data
1
006 - Special computer methods
1
140 - Specific philosophical schools
7
150 - Psychology
1
160 - Logic
1
170 - Ethics
1
200 - Religion
1
300 - Social sciences
13
301 - Sociology & anthropology
3
302 - Social interaction
1
304 - Factors affecting social behavior
3
320 - Political science
12
330 - Economics
24
331 - Labor economics
3
333 - Economics of land & energy
4
338 - Production
3
339 - Macroeconomics & related topics
1
340 - Law
8
351 - Public administration
1
355 - Military science
1
363 - Other social problems & services
13
370 - Education
24
371 - Schools & their activities; special education
1
380 - Commerce, communications & transportation
3
400 - Language
1
410 - Linguistics
1
500 - Natural sciences & mathematics
1
510 - Mathematics
1
511 - General principles of mathematics
1
519 - Probabilities & applied mathematics
2
520 - Astronomy & allied sciences
1
540 - Chemistry & allied sciences
1
551 - Geology, hydrology & meteorology
4
600 - Technology
12
610 - Medicine & health
2
613 - Personal health & safety
1
614 - Incidence & prevention of disease
1
615 - Pharmacology & therapeutics
1
616 - Diseases
11
617 - Surgery & related medical specialties
1
620 - Engineering & allied operations
2
621 - Applied physics
1
629 - Other branches of engineering
2
630 - Agriculture & related technologies
1
641 - Food & drink
1
650 - Management & auxiliary services
4
more ...