Classification
100 - Philosophy & psychology
320 - Political science
330 - Economics
2
333 - Economics of land & energy
2
363 - Other social problems & services
576 - Genetics & evolution
600 - Technology
900 - History & geography
2
300 - Social sciences
1
350 - Public administration & military science
1
380 - Commerce, communications & transportation
1
581 - Specific topics in natural history
1
610 - Medicine & health
1
700 - The arts; fine & decorative arts
1