Classification
100 - Philosophy & psychology
170 - Ethics
363 - Other social problems & services
320 - Political science
15
700 - The arts; fine & decorative arts
10
200 - Religion
9
330 - Economics
9
140 - Specific philosophical schools
8
333 - Economics of land & energy
7
300 - Social sciences
6
581 - Specific topics in natural history
6
340 - Law
5
610 - Medicine & health
5
551 - Geology, hydrology & meteorology
4
900 - History & geography
4
500 - Natural sciences & mathematics
3
600 - Technology
3
370 - Education
2
530 - Physics
2
620 - Engineering & allied operations
2
630 - Agriculture & related technologies
2
120 - Epistemology, causation & humankind
1
301 - Sociology & anthropology
1
361 - Social problems & social welfare in general
1
380 - Commerce, communications & transportation
1
580 - Plants (Botany)
1
590 - Animals (Zoology)
1
658 - General management
1
800 - Literature & rhetoric
1