Classification
330 - Economics
320 - Political science
142
900 - History & geography
94
333 - Economics of land & energy
90
363 - Other social problems & services
45
300 - Social sciences
38
140 - Specific philosophical schools
34
340 - Law
33
700 - The arts; fine & decorative arts
33
100 - Philosophy & psychology
30
380 - Commerce, communications & transportation
30
600 - Technology
28
301 - Sociology & anthropology
15
304 - Factors affecting social behavior
15
551 - Geology, hydrology & meteorology
15
581 - Specific topics in natural history
15
620 - Engineering & allied operations
15
370 - Education
14
630 - Agriculture & related technologies
14
000 - Computer science, information & general works
11
170 - Ethics
9
361 - Social problems & social welfare in general
8
576 - Genetics & evolution
8
720 - Architecture
8
200 - Religion
7
610 - Medicine & health
7
350 - Public administration & military science
5
500 - Natural sciences & mathematics
5
800 - Literature & rhetoric
5
400 - Language
4
410 - Linguistics
3
657 - Accounting
3
780 - Music
3
297 - Islam, Babism & Bahai Faith
2
360 - Social problems & services; associations
2
550 - Earth sciences
2
580 - Plants (Botany)
2
658 - General management
2
791 - Public performances
2
336 - Public finance
1
364 - Criminology
1