Classification
330 - Economics
900 - History & geography
320 - Political science
6,844
576 - Genetics & evolution
1,331
300 - Social sciences
1,121
340 - Law
640
700 - The arts; fine & decorative arts
432
600 - Technology
287
620 - Engineering & allied operations
252
333 - Economics of land & energy
244
363 - Other social problems & services
142
630 - Agriculture & related technologies
122
380 - Commerce, communications & transportation
121
000 - Computer science, information & general works
107
100 - Philosophy & psychology
97
370 - Education
87
200 - Religion
81
610 - Medicine & health
77
140 - Specific philosophical schools
69
800 - Literature & rhetoric
61
580 - Plants (Botany)
44
720 - Architecture
41
170 - Ethics
37
551 - Geology, hydrology & meteorology
37
301 - Sociology & anthropology
35
400 - Language
34
658 - General management
32
304 - Factors affecting social behavior
29
500 - Natural sciences & mathematics
27
780 - Music
20
581 - Specific topics in natural history
18
410 - Linguistics
14
160 - Logic
12
414 - Phonology & phonetics
11
530 - Physics
11
540 - Chemistry & allied sciences
11
920 - Biography, genealogy & insignia
11
770 - Photography, photographs & computer art
9
336 - Public finance
8
350 - Public administration & military science
7
657 - Accounting
7
297 - Islam, Babism & Bahai Faith
6
361 - Social problems & social welfare in general
6
550 - Earth sciences
5
360 - Social problems & services; associations
3
615 - Pharmacology & therapeutics
3
791 - Public performances
3
120 - Epistemology, causation & humankind
2
364 - Criminology
2
520 - Astronomy & allied sciences
2
more ...