Classification
363 - Other social problems & services
326
628 - Sanitary & municipal engineering
280
577 - Ecology
86
333 - Economics of land & energy
75
620 - Engineering & allied operations
70
660 - Chemical engineering
60
551 - Geology, hydrology & meteorology
59
621 - Applied physics
52
624 - Civil engineering
43
304 - Factors affecting social behavior
29
579 - Microorganisms, fungi & algae
20
572 - Biochemistry
15
630 - Agriculture & related technologies
15
338 - Production
14
631 - Techniques, equipment & materials
13
910 - Geography & travel
13
550 - Earth sciences
12
541 - Physical chemistry
10
670 - Manufacturing
10
658 - General management
8
613 - Personal health & safety
7
641 - Food & drink
7
664 - Food technology
7
690 - Buildings
7
549 - Mineralogy
6
615 - Pharmacology & therapeutics
6
629 - Other branches of engineering
6
547 - Organic chemistry
5
614 - Incidence & prevention of disease
5
691 - Building materials
5
003 - Systems
4
519 - Probabilities & applied mathematics
4
539 - Modern physics
4
546 - Inorganic chemistry
4
344 - Labor, social, education & cultural law
3
526 - Mathematical geography
3
530 - Physics
3
571 - Physiology & related subjects
3
610 - Medicine & health
3
616 - Diseases
3
696 - Utilities
3
720 - Architecture
3
006 - Special computer methods
2
352 - General considerations of public administration
2
500 - Natural sciences & mathematics
2
540 - Chemistry & allied sciences
2
570 - Life sciences; biology
2
004 - Data processing & computer science
1
170 - Ethics
1
300 - Social sciences
1
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