Classification
330 - Economics
3,791
551 - Geology, hydrology & meteorology
385
363 - Other social problems & services
319
333 - Economics of land & energy
105
610 - Medicine & health
94
700 - The arts; fine & decorative arts
89
624 - Civil engineering
77
550 - Earth sciences
63
320 - Political science
53
900 - History & geography
52
910 - Geography & travel
50
620 - Engineering & allied operations
49
600 - Technology
48
000 - Computer science, information & general works
47
140 - Specific philosophical schools
33
380 - Commerce, communications & transportation
33
658 - General management
33
360 - Social problems & services; associations
30
300 - Social sciences
25
304 - Factors affecting social behavior
21
500 - Natural sciences & mathematics
21
340 - Law
19
621 - Applied physics
16
100 - Philosophy & psychology
15
628 - Sanitary & municipal engineering
14
370 - Education
13
576 - Genetics & evolution
13
307 - Communities
12
526 - Mathematical geography
12
368 - Insurance
11
338 - Production
10
400 - Language
10
720 - Architecture
10
581 - Specific topics in natural history
9
800 - Literature & rhetoric
9
005 - Computer programming, programs & data
8
331 - Labor economics
8
577 - Ecology
8
580 - Plants (Botany)
8
361 - Social problems & social welfare in general
7
301 - Sociology & anthropology
6
414 - Phonology & phonetics
6
630 - Agriculture & related technologies
6
003 - Systems
5
170 - Ethics
5
200 - Religion
5
362 - Social welfare problems & services
4
410 - Linguistics
4
616 - Diseases
4
629 - Other branches of engineering
4
more ...