Classification
970 - History of North America
224
330 - Economics
128
320 - Political science
105
900 - History & geography
88
820 - English & Old English literatures
68
340 - Law
54
301 - Sociology & anthropology
22
620 - Engineering & allied operations
13
200 - Religion
12
576 - Genetics & evolution
11
300 - Social sciences
10
360 - Social problems & services; associations
9
610 - Medicine & health
8
305 - Social groups
6
323 - Civil & political rights
5
338 - Production
5
400 - Language
5
910 - Geography & travel
5
973 - United States
5
140 - Specific philosophical schools
4
304 - Factors affecting social behavior
4
370 - Education
4
628 - Sanitary & municipal engineering
4
700 - The arts; fine & decorative arts
4
000 - Computer science, information & general works
3
240 - Christian moral & devotional theology
3
280 - Christian denominations & sects
3
299 - Religions not provided for elsewhere
3
337 - International economics
3
346 - Private law
3
363 - Other social problems & services
3
490 - Other languages
3
570 - Life sciences; biology
3
580 - Plants (Botany)
3
632 - Plant injuries, diseases & pests
3
658 - General management
3
800 - Literature & rhetoric
3
979 - Great Basin & Pacific Slope region
3
100 - Philosophy & psychology
2
170 - Ethics
2
297 - Islam, Babism & Bahai Faith
2
303 - Social processes
2
333 - Economics of land & energy
2
342 - Constitutional & administrative law
2
362 - Social welfare problems & services
2
500 - Natural sciences & mathematics
2
551 - Geology, hydrology & meteorology
2
571 - Physiology & related subjects
2
598 - Birds
2
810 - American literature in English
2
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