Classification
320 - Political science
363 - Other social problems & services
380 - Commerce, communications & transportation
551 - Geology, hydrology & meteorology
900 - History & geography
333 - Economics of land & energy
4
000 - Computer science, information & general works
3
330 - Economics
3
370 - Education
3
600 - Technology
3
700 - The arts; fine & decorative arts
3
610 - Medicine & health
2
720 - Architecture
2
140 - Specific philosophical schools
1
414 - Phonology & phonetics
1
581 - Specific topics in natural history
1
620 - Engineering & allied operations
1