Classification
630 - Agriculture & related technologies
600 - Technology
45
620 - Engineering & allied operations
43
330 - Economics
31
333 - Economics of land & energy
21
363 - Other social problems & services
19
900 - History & geography
17
320 - Political science
16
300 - Social sciences
15
580 - Plants (Botany)
11
581 - Specific topics in natural history
6
380 - Commerce, communications & transportation
5
610 - Medicine & health
5
100 - Philosophy & psychology
4
140 - Specific philosophical schools
4
340 - Law
4
700 - The arts; fine & decorative arts
4
200 - Religion
3
301 - Sociology & anthropology
2
304 - Factors affecting social behavior
2
551 - Geology, hydrology & meteorology
2
800 - Literature & rhetoric
2
000 - Computer science, information & general works
1
170 - Ethics
1
364 - Criminology
1
500 - Natural sciences & mathematics
1
530 - Physics
1
540 - Chemistry & allied sciences
1
550 - Earth sciences
1
576 - Genetics & evolution
1
590 - Animals (Zoology)
1