Classification
330 - Economics
64
320 - Political science
59
340 - Law
53
820 - English & Old English literatures
21
970 - History of North America
20
551 - Geology, hydrology & meteorology
18
780 - Music
17
900 - History & geography
16
333 - Economics of land & energy
15
363 - Other social problems & services
15
700 - The arts; fine & decorative arts
11
304 - Factors affecting social behavior
10
577 - Ecology
9
301 - Sociology & anthropology
8
610 - Medicine & health
6
620 - Engineering & allied operations
6
781 - General principles & musical forms
6
782 - Vocal music
6
920 - Biography, genealogy & insignia
6
930 - History of ancient world to ca. 499
6
500 - Natural sciences & mathematics
5
580 - Plants (Botany)
5
910 - Geography & travel
5
000 - Computer science, information & general works
4
628 - Sanitary & municipal engineering
4
307 - Communities
3
332 - Financial economics
3
370 - Education
3
549 - Mineralogy
3
553 - Economic geology
3
630 - Agriculture & related technologies
3
973 - United States
3
005 - Computer programming, programs & data
2
210 - Philosophy & theory of religion
2
300 - Social sciences
2
306 - Culture & institutions
2
371 - Schools & their activities; special education
2
540 - Chemistry & allied sciences
2
550 - Earth sciences
2
576 - Genetics & evolution
2
600 - Technology
2
613 - Personal health & safety
2
614 - Incidence & prevention of disease
2
624 - Civil engineering
2
632 - Plant injuries, diseases & pests
2
658 - General management
2
001 - Knowledge
1
003 - Systems
1
004 - Data processing & computer science
1
006 - Special computer methods
1
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