Classification
330 - Economics
643
320 - Political science
320
006 - Special computer methods
264
900 - History & geography
190
333 - Economics of land & energy
184
004 - Data processing & computer science
163
820 - English & Old English literatures
146
005 - Computer programming, programs & data
144
304 - Factors affecting social behavior
116
610 - Medicine & health
116
300 - Social sciences
104
363 - Other social problems & services
98
340 - Law
88
658 - General management
86
620 - Engineering & allied operations
84
700 - The arts; fine & decorative arts
81
370 - Education
78
551 - Geology, hydrology & meteorology
65
621 - Applied physics
62
600 - Technology
53
306 - Culture & institutions
52
338 - Production
51
530 - Physics
49
577 - Ecology
48
000 - Computer science, information & general works
46
940 - History of Europe
41
800 - Literature & rhetoric
40
515 - Analysis
39
616 - Diseases
38
336 - Public finance
37
380 - Commerce, communications & transportation
37
629 - Other branches of engineering
34
630 - Agriculture & related technologies
34
500 - Natural sciences & mathematics
33
305 - Social groups
32
301 - Sociology & anthropology
31
510 - Mathematics
27
580 - Plants (Botany)
27
331 - Labor economics
26
550 - Earth sciences
26
140 - Specific philosophical schools
24
003 - Systems
23
327 - International relations
23
519 - Probabilities & applied mathematics
23
400 - Language
22
303 - Social processes
21
576 - Genetics & evolution
20
200 - Religion
19
364 - Criminology
19
100 - Philosophy & psychology
18
more ...