Classification
005 - Computer programming, programs & data
38
004 - Data processing & computer science
29
006 - Special computer methods
26
616 - Diseases
26
621 - Applied physics
22
658 - General management
22
620 - Engineering & allied operations
20
330 - Economics
18
610 - Medicine & health
13
155 - Differential & developmental psychology
10
304 - Factors affecting social behavior
10
333 - Economics of land & energy
10
500 - Natural sciences & mathematics
10
617 - Surgery & related medical specialties
9
300 - Social sciences
8
331 - Labor economics
7
519 - Probabilities & applied mathematics
7
539 - Modern physics
7
613 - Personal health & safety
7
001 - Knowledge
6
150 - Psychology
6
302 - Social interaction
6
306 - Culture & institutions
6
510 - Mathematics
6
370 - Education
5
530 - Physics
5
571 - Physiology & related subjects
5
577 - Ecology
5
612 - Human physiology
5
629 - Other branches of engineering
5
660 - Chemical engineering
5
910 - Geography & travel
5
003 - Systems
4
025 - Library operations
4
301 - Sociology & anthropology
4
338 - Production
4
371 - Schools & their activities; special education
4
520 - Astronomy & allied sciences
4
551 - Geology, hydrology & meteorology
4
614 - Incidence & prevention of disease
4
327 - International relations
3
374 - Adult education
3
380 - Commerce, communications & transportation
3
507 - Education, research & related topics
3
541 - Physical chemistry
3
572 - Biochemistry
3
618 - Gynecology, obstetrics, pediatrics & geriatrics
3
630 - Agriculture & related technologies
3
809 - History, description & criticism
3
000 - Computer science, information & general works
2
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