Classification
580 - Plants (Botany)
1,834
581 - Specific topics in natural history
426
571 - Physiology & related subjects
325
630 - Agriculture & related technologies
282
572 - Biochemistry
194
616 - Diseases
177
577 - Ecology
119
500 - Natural sciences & mathematics
106
547 - Organic chemistry
102
579 - Microorganisms, fungi & algae
74
610 - Medicine & health
71
660 - Chemical engineering
64
333 - Economics of land & energy
63
330 - Economics
51
615 - Pharmacology & therapeutics
50
570 - Life sciences; biology
49
363 - Other social problems & services
41
320 - Political science
38
551 - Geology, hydrology & meteorology
36
576 - Genetics & evolution
35
631 - Techniques, equipment & materials
32
634 - Orchards, fruits & forestry
31
590 - Animals (Zoology)
28
664 - Food technology
25
600 - Technology
22
620 - Engineering & allied operations
22
000 - Computer science, information & general works
20
700 - The arts; fine & decorative arts
20
641 - Food & drink
19
380 - Commerce, communications & transportation
14
578 - Natural history of organisms
14
900 - History & geography
13
612 - Human physiology
11
414 - Phonology & phonetics
10
613 - Personal health & safety
9
300 - Social sciences
8
540 - Chemistry & allied sciences
8
592 - Invertebrates
6
720 - Architecture
6
820 - English & Old English literatures
6
560 - Paleontology; paleozoology
5
614 - Incidence & prevention of disease
5
910 - Geography & travel
5
617 - Surgery & related medical specialties
4
632 - Plant injuries, diseases & pests
4
006 - Special computer methods
3
140 - Specific philosophical schools
3
301 - Sociology & anthropology
3
304 - Factors affecting social behavior
3
530 - Physics
3
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