Classification
330 - Economics
1,892
304 - Factors affecting social behavior
424
320 - Political science
254
610 - Medicine & health
209
700 - The arts; fine & decorative arts
152
000 - Computer science, information & general works
138
333 - Economics of land & energy
125
570 - Life sciences; biology
120
300 - Social sciences
96
363 - Other social problems & services
96
900 - History & geography
93
576 - Genetics & evolution
75
600 - Technology
75
577 - Ecology
71
140 - Specific philosophical schools
70
580 - Plants (Botany)
65
380 - Commerce, communications & transportation
63
551 - Geology, hydrology & meteorology
51
301 - Sociology & anthropology
48
620 - Engineering & allied operations
44
581 - Specific topics in natural history
42
305 - Social groups
37
370 - Education
37
306 - Culture & institutions
34
340 - Law
34
519 - Probabilities & applied mathematics
31
630 - Agriculture & related technologies
30
658 - General management
30
820 - English & Old English literatures
29
500 - Natural sciences & mathematics
27
338 - Production
24
579 - Microorganisms, fungi & algae
23
100 - Philosophy & psychology
21
515 - Analysis
21
331 - Labor economics
20
361 - Social problems & social welfare in general
18
571 - Physiology & related subjects
18
170 - Ethics
17
591 - Specific topics in natural history
16
613 - Personal health & safety
16
614 - Incidence & prevention of disease
16
414 - Phonology & phonetics
15
720 - Architecture
15
307 - Communities
14
612 - Human physiology
14
339 - Macroeconomics & related topics
13
400 - Language
13
540 - Chemistry & allied sciences
13
200 - Religion
11
616 - Diseases
11
more ...