Classification
330 - Economics
229
320 - Political science
58
333 - Economics of land & energy
34
370 - Education
21
820 - English & Old English literatures
20
610 - Medicine & health
19
363 - Other social problems & services
17
304 - Factors affecting social behavior
16
600 - Technology
16
140 - Specific philosophical schools
11
700 - The arts; fine & decorative arts
10
900 - History & geography
10
301 - Sociology & anthropology
8
380 - Commerce, communications & transportation
7
336 - Public finance
6
000 - Computer science, information & general works
5
300 - Social sciences
5
100 - Philosophy & psychology
4
303 - Social processes
4
340 - Law
4
581 - Specific topics in natural history
4
170 - Ethics
3
200 - Religion
3
306 - Culture & institutions
3
338 - Production
3
551 - Geology, hydrology & meteorology
3
986 - Colombia & Ecuador
3
307 - Communities
2
339 - Macroeconomics & related topics
2
342 - Constitutional & administrative law
2
576 - Genetics & evolution
2
580 - Plants (Botany)
2
628 - Sanitary & municipal engineering
2
630 - Agriculture & related technologies
2
800 - Literature & rhetoric
2
970 - History of North America
2
120 - Epistemology, causation & humankind
1
322 - Relation of state to organized groups
1
331 - Labor economics
1
351 - Public administration
1
355 - Military science
1
362 - Social welfare problems & services
1
378 - Higher education
1
381 - Commerce
1
400 - Language
1
500 - Natural sciences & mathematics
1
526 - Mathematical geography
1
615 - Pharmacology & therapeutics
1
620 - Engineering & allied operations
1
720 - Architecture
1
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