Classification
520 - Astronomy & allied sciences
250
523 - Specific celestial bodies & phenomena
68
500 - Natural sciences & mathematics
48
572 - Biochemistry
17
615 - Pharmacology & therapeutics
17
616 - Diseases
17
006 - Special computer methods
13
530 - Physics
13
330 - Economics
12
509 - Historical, geographic & persons treatment
12
571 - Physiology & related subjects
12
005 - Computer programming, programs & data
11
629 - Other branches of engineering
11
820 - English & Old English literatures
11
363 - Other social problems & services
10
551 - Geology, hydrology & meteorology
10
576 - Genetics & evolution
9
004 - Data processing & computer science
8
910 - Geography & travel
8
900 - History & geography
7
000 - Computer science, information & general works
6
510 - Mathematics
6
610 - Medicine & health
6
620 - Engineering & allied operations
6
621 - Applied physics
6
700 - The arts; fine & decorative arts
6
130 - Parapsychology & occultism
5
519 - Probabilities & applied mathematics
5
658 - General management
5
230 - Christianity & Christian theology
4
331 - Labor economics
4
370 - Education
4
539 - Modern physics
4
580 - Plants (Botany)
4
600 - Technology
4
612 - Human physiology
4
790 - Recreational & performing arts
4
030 - General encyclopedic works
3
140 - Specific philosophical schools
3
302 - Social interaction
3
501 - Philosophy & theory
3
522 - Techniques, equipment & materials
3
540 - Chemistry & allied sciences
3
560 - Paleontology; paleozoology
3
745 - Decorative arts
3
150 - Psychology
2
220 - Bible
2
320 - Political science
2
333 - Economics of land & energy
2
381 - Commerce
2
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