Classification
330 - Economics
1,054
304 - Factors affecting social behavior
462
320 - Political science
397
610 - Medicine & health
219
700 - The arts; fine & decorative arts
162
300 - Social sciences
150
000 - Computer science, information & general works
138
333 - Economics of land & energy
123
570 - Life sciences; biology
121
900 - History & geography
107
363 - Other social problems & services
102
140 - Specific philosophical schools
81
577 - Ecology
81
576 - Genetics & evolution
78
600 - Technology
73
580 - Plants (Botany)
65
380 - Commerce, communications & transportation
62
301 - Sociology & anthropology
56
340 - Law
50
551 - Geology, hydrology & meteorology
50
630 - Agriculture & related technologies
46
620 - Engineering & allied operations
45
306 - Culture & institutions
43
581 - Specific topics in natural history
41
370 - Education
40
658 - General management
40
305 - Social groups
39
338 - Production
34
519 - Probabilities & applied mathematics
33
100 - Philosophy & psychology
30
820 - English & Old English literatures
30
500 - Natural sciences & mathematics
26
571 - Physiology & related subjects
23
579 - Microorganisms, fungi & algae
23
331 - Labor economics
21
361 - Social problems & social welfare in general
21
515 - Analysis
20
170 - Ethics
18
307 - Communities
17
591 - Specific topics in natural history
17
414 - Phonology & phonetics
15
613 - Personal health & safety
15
614 - Incidence & prevention of disease
15
612 - Human physiology
14
540 - Chemistry & allied sciences
13
720 - Architecture
13
339 - Macroeconomics & related topics
12
400 - Language
12
800 - Literature & rhetoric
12
200 - Religion
11
more ...