Classification
630 - Agriculture & related technologies
330 - Economics
2,631
320 - Political science
2,490
300 - Social sciences
896
600 - Technology
532
620 - Engineering & allied operations
444
363 - Other social problems & services
426
333 - Economics of land & energy
361
700 - The arts; fine & decorative arts
278
000 - Computer science, information & general works
229
900 - History & geography
221
610 - Medicine & health
208
580 - Plants (Botany)
199
380 - Commerce, communications & transportation
156
340 - Law
153
551 - Geology, hydrology & meteorology
110
581 - Specific topics in natural history
100
140 - Specific philosophical schools
58
304 - Factors affecting social behavior
51
370 - Education
50
540 - Chemistry & allied sciences
40
500 - Natural sciences & mathematics
38
576 - Genetics & evolution
35
301 - Sociology & anthropology
31
100 - Philosophy & psychology
26
800 - Literature & rhetoric
25
720 - Architecture
23
414 - Phonology & phonetics
22
658 - General management
22
200 - Religion
18
664 - Food technology
16
612 - Human physiology
15
170 - Ethics
14
361 - Social problems & social welfare in general
14
530 - Physics
11
400 - Language
9
336 - Public finance
8
410 - Linguistics
8
550 - Earth sciences
5
590 - Animals (Zoology)
5
657 - Accounting
5
770 - Photography, photographs & computer art
5
160 - Logic
4
338 - Production
4
350 - Public administration & military science
4
780 - Music
4
364 - Criminology
3
297 - Islam, Babism & Bahai Faith
2
520 - Astronomy & allied sciences
2
307 - Communities
1
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