Classification
333 - Economics of land & energy
125
621 - Applied physics
43
338 - Production
38
330 - Economics
13
304 - Factors affecting social behavior
11
660 - Chemical engineering
10
363 - Other social problems & services
9
620 - Engineering & allied operations
8
628 - Sanitary & municipal engineering
8
658 - General management
8
551 - Geology, hydrology & meteorology
7
600 - Technology
6
577 - Ecology
5
670 - Manufacturing
4
320 - Political science
3
624 - Civil engineering
3
327 - International relations
2
332 - Financial economics
2
550 - Earth sciences
2
627 - Hydraulic engineering
2
630 - Agriculture & related technologies
2
631 - Techniques, equipment & materials
2
634 - Orchards, fruits & forestry
2
140 - Specific philosophical schools
1
174 - Occupational ethics
1
300 - Social sciences
1
306 - Culture & institutions
1
321 - Systems of governments & states
1
342 - Constitutional & administrative law
1
350 - Public administration & military science
1
361 - Social problems & social welfare in general
1
387 - Water, air & space transportation
1
388 - Transportation; ground transportation
1
519 - Probabilities & applied mathematics
1
546 - Inorganic chemistry
1
547 - Organic chemistry
1
549 - Mineralogy
1
553 - Economic geology
1
570 - Life sciences; biology
1
629 - Other branches of engineering
1
657 - Accounting
1
662 - Explosives, fuels & related products
1
690 - Buildings
1
700 - The arts; fine & decorative arts
1