Classification
000 - Computer science, information & general works
330 - Economics
551 - Geology, hydrology & meteorology
630 - Agriculture & related technologies
333 - Economics of land & energy
5
363 - Other social problems & services
5
320 - Political science
4
700 - The arts; fine & decorative arts
3
580 - Plants (Botany)
2
581 - Specific topics in natural history
2
600 - Technology
2
610 - Medicine & health
2
140 - Specific philosophical schools
1
304 - Factors affecting social behavior
1
340 - Law
1
370 - Education
1
380 - Commerce, communications & transportation
1
620 - Engineering & allied operations
1
800 - Literature & rhetoric
1