Classification
520 - Astronomy & allied sciences
1,403
523 - Specific celestial bodies & phenomena
242
500 - Natural sciences & mathematics
233
820 - English & Old English literatures
111
530 - Physics
95
510 - Mathematics
61
910 - Geography & travel
44
970 - History of North America
40
509 - Historical, geographic & persons treatment
36
620 - Engineering & allied operations
29
600 - Technology
28
330 - Economics
25
006 - Special computer methods
24
551 - Geology, hydrology & meteorology
24
539 - Modern physics
21
550 - Earth sciences
21
900 - History & geography
21
320 - Political science
18
621 - Applied physics
17
501 - Philosophy & theory
16
300 - Social sciences
15
519 - Probabilities & applied mathematics
15
629 - Other branches of engineering
15
130 - Parapsychology & occultism
14
522 - Techniques, equipment & materials
14
576 - Genetics & evolution
13
770 - Photography, photographs & computer art
12
030 - General encyclopedic works
10
001 - Knowledge
9
610 - Medicine & health
9
680 - Manufacture for specific uses
9
005 - Computer programming, programs & data
7
333 - Economics of land & energy
7
516 - Geometry
7
515 - Analysis
6
650 - Management & auxiliary services
6
200 - Religion
5
526 - Mathematical geography
5
003 - Systems
4
004 - Data processing & computer science
4
512 - Algebra
4
531 - Classical mechanics; solid mechanics
4
541 - Physical chemistry
4
616 - Diseases
4
658 - General management
4
000 - Computer science, information & general works
3
020 - Library & information sciences
3
100 - Philosophy & psychology
3
220 - Bible
3
260 - Social & ecclesiastical theology
3
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