Classification
330 - Economics
63
300 - Social sciences
46
320 - Political science
31
900 - History & geography
20
340 - Law
16
304 - Factors affecting social behavior
13
700 - The arts; fine & decorative arts
12
380 - Commerce, communications & transportation
11
370 - Education
10
333 - Economics of land & energy
9
610 - Medicine & health
9
100 - Philosophy & psychology
6
361 - Social problems & social welfare in general
6
600 - Technology
6
140 - Specific philosophical schools
5
301 - Sociology & anthropology
5
630 - Agriculture & related technologies
4
170 - Ethics
3
620 - Engineering & allied operations
3
200 - Religion
2
360 - Social problems & services; associations
2
363 - Other social problems & services
2
800 - Literature & rhetoric
2
120 - Epistemology, causation & humankind
1
350 - Public administration & military science
1
400 - Language
1
551 - Geology, hydrology & meteorology
1
657 - Accounting
1
770 - Photography, photographs & computer art
1