Classification
170 - Ethics
330 - Economics
42
320 - Political science
20
100 - Philosophy & psychology
16
333 - Economics of land & energy
12
300 - Social sciences
11
363 - Other social problems & services
11
340 - Law
8
700 - The arts; fine & decorative arts
8
140 - Specific philosophical schools
7
551 - Geology, hydrology & meteorology
5
361 - Social problems & social welfare in general
4
370 - Education
4
600 - Technology
4
610 - Medicine & health
4
900 - History & geography
4
000 - Computer science, information & general works
3
380 - Commerce, communications & transportation
3
620 - Engineering & allied operations
2
658 - General management
2
720 - Architecture
2
158 - Applied psychology
1
200 - Religion
1
301 - Sociology & anthropology
1
304 - Factors affecting social behavior
1
350 - Public administration & military science
1
500 - Natural sciences & mathematics
1
581 - Specific topics in natural history
1
813 - American fiction in English
1