Classification
610 - Medicine & health
306 - Culture & institutions
62
700 - The arts; fine & decorative arts
46
000 - Computer science, information & general works
37
333 - Economics of land & energy
31
330 - Economics
29
620 - Engineering & allied operations
26
380 - Commerce, communications & transportation
25
580 - Plants (Botany)
25
600 - Technology
25
140 - Specific philosophical schools
21
363 - Other social problems & services
14
362 - Social welfare problems & services
12
370 - Education
11
540 - Chemistry & allied sciences
10
616 - Diseases
10
551 - Geology, hydrology & meteorology
9
900 - History & geography
9
100 - Philosophy & psychology
8
576 - Genetics & evolution
8
630 - Agriculture & related technologies
8
618 - Gynecology, obstetrics, pediatrics & geriatrics
7
361 - Social problems & social welfare in general
6
612 - Human physiology
6
414 - Phonology & phonetics
5
615 - Pharmacology & therapeutics
5
500 - Natural sciences & mathematics
4
581 - Specific topics in natural history
4
614 - Incidence & prevention of disease
4
658 - General management
4
300 - Social sciences
3
340 - Law
3
613 - Personal health & safety
3
338 - Production
2
372 - Elementary education
2
400 - Language
2
720 - Architecture
2
001 - Knowledge
1
150 - Psychology
1
174 - Occupational ethics
1
304 - Factors affecting social behavior
1
320 - Political science
1
331 - Labor economics
1
353 - Specific fields of public administration
1
355 - Military science
1
365 - Penal & related institutions
1
371 - Schools & their activities; special education
1
394 - General customs
1
509 - Historical, geographic & persons treatment
1
519 - Probabilities & applied mathematics
1
more ...