Classification
363 - Other social problems & services
64
330 - Economics
49
333 - Economics of land & energy
24
628 - Sanitary & municipal engineering
20
000 - Computer science, information & general works
12
700 - The arts; fine & decorative arts
12
620 - Engineering & allied operations
11
551 - Geology, hydrology & meteorology
10
658 - General management
10
600 - Technology
9
304 - Factors affecting social behavior
8
340 - Law
8
630 - Agriculture & related technologies
8
320 - Political science
7
338 - Production
7
610 - Medicine & health
6
140 - Specific philosophical schools
5
380 - Commerce, communications & transportation
5
500 - Natural sciences & mathematics
5
580 - Plants (Botany)
5
632 - Plant injuries, diseases & pests
5
800 - Literature & rhetoric
5
540 - Chemistry & allied sciences
4
577 - Ecology
4
581 - Specific topics in natural history
4
627 - Hydraulic engineering
4
631 - Techniques, equipment & materials
4
670 - Manufacturing
4
900 - History & geography
4
344 - Labor, social, education & cultural law
3
624 - Civil engineering
3
791 - Public performances
3
300 - Social sciences
2
331 - Labor economics
2
361 - Social problems & social welfare in general
2
541 - Physical chemistry
2
542 - Techniques, equipment & materials
2
621 - Applied physics
2
660 - Chemical engineering
2
001 - Knowledge
1
170 - Ethics
1
261 - Social theology
1
297 - Islam, Babism & Bahai Faith
1
301 - Sociology & anthropology
1
303 - Social processes
1
307 - Communities
1
336 - Public finance
1
341 - Law of nations
1
346 - Private law
1
370 - Education
1
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