Classification
355 - Military science
45
362 - Social welfare problems & services
29
358 - Air & other specialized forces
20
363 - Other social problems & services
15
616 - Diseases
7
327 - International relations
6
610 - Medicine & health
6
371 - Schools & their activities; special education
5
332 - Financial economics
4
368 - Insurance
4
324 - The political process
3
331 - Labor economics
3
333 - Economics of land & energy
3
338 - Production
3
352 - General considerations of public administration
3
372 - Elementary education
3
379 - Public policy issues in education
3
618 - Gynecology, obstetrics, pediatrics & geriatrics
3
623 - Military & nautical engineering
3
658 - General management
3
303 - Social processes
2
305 - Social groups
2
306 - Culture & institutions
2
322 - Relation of state to organized groups
2
353 - Specific fields of public administration
2
356 - Infantry forces & warfare
2
359 - Sea forces & warfare
2
370 - Education
2
388 - Transportation; ground transportation
2
614 - Incidence & prevention of disease
2
615 - Pharmacology & therapeutics
2
617 - Surgery & related medical specialties
2
005 - Computer programming, programs & data
1
025 - Library operations
1
155 - Differential & developmental psychology
1
301 - Sociology & anthropology
1
302 - Social interaction
1
323 - Civil & political rights
1
330 - Economics
1
341 - Law of nations
1
343 - Military, tax, trade & industrial law
1
347 - Civil procedure & courts
1
364 - Criminology
1
365 - Penal & related institutions
1
381 - Commerce
1
384 - Communications; telecommunication
1
510 - Mathematics
1
620 - Engineering & allied operations
1
629 - Other branches of engineering
1
649 - Child rearing & home care of persons
1
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