Classification
333 - Economics of land & energy
363 - Other social problems & services
320 - Political science
5
551 - Geology, hydrology & meteorology
4
330 - Economics
3
581 - Specific topics in natural history
3
600 - Technology
3
620 - Engineering & allied operations
2
100 - Philosophy & psychology
1
140 - Specific philosophical schools
1
340 - Law
1
700 - The arts; fine & decorative arts
1