Classification
170 - Ethics
330 - Economics
551 - Geology, hydrology & meteorology
363 - Other social problems & services
7
100 - Philosophy & psychology
4
320 - Political science
4
000 - Computer science, information & general works
3
333 - Economics of land & energy
3
380 - Commerce, communications & transportation
3
140 - Specific philosophical schools
2
581 - Specific topics in natural history
2
620 - Engineering & allied operations
2
700 - The arts; fine & decorative arts
2
900 - History & geography
2
300 - Social sciences
1
370 - Education
1
414 - Phonology & phonetics
1
500 - Natural sciences & mathematics
1
600 - Technology
1
610 - Medicine & health
1
658 - General management
1
720 - Architecture
1