Classification
621 - Applied physics
174
333 - Economics of land & energy
68
551 - Geology, hydrology & meteorology
68
662 - Explosives, fuels & related products
51
330 - Economics
31
620 - Engineering & allied operations
27
363 - Other social problems & services
26
624 - Civil engineering
24
660 - Chemical engineering
24
549 - Mineralogy
14
600 - Technology
14
550 - Earth sciences
13
338 - Production
10
526 - Mathematical geography
9
553 - Economic geology
9
629 - Other branches of engineering
8
541 - Physical chemistry
7
628 - Sanitary & municipal engineering
7
900 - History & geography
7
320 - Political science
6
380 - Commerce, communications & transportation
6
000 - Computer science, information & general works
5
577 - Ecology
5
627 - Hydraulic engineering
5
700 - The arts; fine & decorative arts
5
540 - Chemistry & allied sciences
4
560 - Paleontology; paleozoology
4
610 - Medicine & health
4
665 - Industrial oils, fats, waxes & gases
4
140 - Specific philosophical schools
3
580 - Plants (Botany)
3
003 - Systems
2
344 - Labor, social, education & cultural law
2
530 - Physics
2
543 - Analytical chemistry
2
547 - Organic chemistry
2
576 - Genetics & evolution
2
622 - Mining & related operations
2
630 - Agriculture & related technologies
2
658 - General management
2
910 - Geography & travel
2
100 - Philosophy & psychology
1
170 - Ethics
1
300 - Social sciences
1
304 - Factors affecting social behavior
1
332 - Financial economics
1
341 - Law of nations
1
393 - Death customs
1
414 - Phonology & phonetics
1
500 - Natural sciences & mathematics
1
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