Classification
333 - Economics of land & energy
330 - Economics
2,019
320 - Political science
1,966
600 - Technology
1,610
700 - The arts; fine & decorative arts
1,405
363 - Other social problems & services
1,394
610 - Medicine & health
1,068
620 - Engineering & allied operations
1,050
000 - Computer science, information & general works
978
900 - History & geography
913
380 - Commerce, communications & transportation
724
370 - Education
488
140 - Specific philosophical schools
455
340 - Law
443
304 - Factors affecting social behavior
430
580 - Plants (Botany)
400
530 - Physics
371
630 - Agriculture & related technologies
331
338 - Production
322
500 - Natural sciences & mathematics
296
551 - Geology, hydrology & meteorology
291
576 - Genetics & evolution
278
100 - Philosophy & psychology
248
540 - Chemistry & allied sciences
228
300 - Social sciences
203
581 - Specific topics in natural history
180
720 - Architecture
147
658 - General management
119
414 - Phonology & phonetics
108
400 - Language
101
800 - Literature & rhetoric
99
336 - Public finance
88
170 - Ethics
78
612 - Human physiology
64
200 - Religion
51
301 - Sociology & anthropology
47
361 - Social problems & social welfare in general
46
410 - Linguistics
44
621 - Applied physics
39
615 - Pharmacology & therapeutics
35
657 - Accounting
26
780 - Music
23
350 - Public administration & military science
22
297 - Islam, Babism & Bahai Faith
19
520 - Astronomy & allied sciences
17
120 - Epistemology, causation & humankind
16
791 - Public performances
15
650 - Management & auxiliary services
14
770 - Photography, photographs & computer art
13
550 - Earth sciences
10
more ...