Classification
900 - History & geography
600 - Technology
450
620 - Engineering & allied operations
445
700 - The arts; fine & decorative arts
308
333 - Economics of land & energy
252
000 - Computer science, information & general works
137
330 - Economics
137
380 - Commerce, communications & transportation
129
363 - Other social problems & services
102
610 - Medicine & health
85
320 - Political science
84
576 - Genetics & evolution
71
140 - Specific philosophical schools
64
580 - Plants (Botany)
62
340 - Law
44
720 - Architecture
43
500 - Natural sciences & mathematics
34
300 - Social sciences
31
530 - Physics
23
551 - Geology, hydrology & meteorology
23
370 - Education
22
800 - Literature & rhetoric
21
400 - Language
16
414 - Phonology & phonetics
16
630 - Agriculture & related technologies
16
658 - General management
16
540 - Chemistry & allied sciences
12
100 - Philosophy & psychology
11
304 - Factors affecting social behavior
9
581 - Specific topics in natural history
8
200 - Religion
6
410 - Linguistics
5
120 - Epistemology, causation & humankind
4
170 - Ethics
4
770 - Photography, photographs & computer art
4
780 - Music
4
301 - Sociology & anthropology
3
550 - Earth sciences
3
160 - Logic
2
297 - Islam, Babism & Bahai Faith
2
350 - Public administration & military science
2
360 - Social problems & services; associations
2
361 - Social problems & social welfare in general
2
590 - Animals (Zoology)
2
650 - Management & auxiliary services
2
336 - Public finance
1
612 - Human physiology
1
614 - Incidence & prevention of disease
1
615 - Pharmacology & therapeutics
1
657 - Accounting
1
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