Classification
500 - Natural sciences & mathematics
238
900 - History & geography
135
330 - Economics
83
320 - Political science
76
363 - Other social problems & services
38
700 - The arts; fine & decorative arts
37
581 - Specific topics in natural history
24
333 - Economics of land & energy
18
577 - Ecology
18
600 - Technology
14
580 - Plants (Botany)
13
610 - Medicine & health
13
620 - Engineering & allied operations
13
230 - Christianity & Christian theology
12
970 - History of North America
12
200 - Religion
11
300 - Social sciences
11
508 - Natural history
11
590 - Animals (Zoology)
10
100 - Philosophy & psychology
9
630 - Agriculture & related technologies
9
000 - Computer science, information & general works
8
570 - Life sciences; biology
8
820 - English & Old English literatures
8
140 - Specific philosophical schools
7
340 - Law
7
910 - Geography & travel
7
920 - Biography, genealogy & insignia
7
540 - Chemistry & allied sciences
6
551 - Geology, hydrology & meteorology
6
400 - Language
5
576 - Genetics & evolution
5
615 - Pharmacology & therapeutics
5
612 - Human physiology
4
930 - History of ancient world to ca. 499
4
030 - General encyclopedic works
3
240 - Christian moral & devotional theology
3
301 - Sociology & anthropology
3
380 - Commerce, communications & transportation
3
520 - Astronomy & allied sciences
3
550 - Earth sciences
3
800 - Literature & rhetoric
3
010 - Bibliography
2
113 - Cosmology
2
130 - Parapsychology & occultism
2
510 - Mathematics
2
578 - Natural history of organisms
2
770 - Photography, photographs & computer art
2
810 - American literature in English
2
020 - Library & information sciences
1
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