Classification
621 - Applied physics
772
333 - Economics of land & energy
209
338 - Production
122
620 - Engineering & allied operations
100
660 - Chemical engineering
47
330 - Economics
43
600 - Technology
40
658 - General management
37
700 - The arts; fine & decorative arts
35
541 - Physical chemistry
33
363 - Other social problems & services
28
629 - Other branches of engineering
25
900 - History & geography
21
624 - Civil engineering
19
720 - Architecture
19
577 - Ecology
18
380 - Commerce, communications & transportation
17
579 - Microorganisms, fungi & algae
14
580 - Plants (Botany)
14
000 - Computer science, information & general works
13
551 - Geology, hydrology & meteorology
13
531 - Classical mechanics; solid mechanics
11
628 - Sanitary & municipal engineering
11
006 - Special computer methods
10
388 - Transportation; ground transportation
10
530 - Physics
9
670 - Manufacturing
8
690 - Buildings
8
519 - Probabilities & applied mathematics
7
320 - Political science
6
500 - Natural sciences & mathematics
6
610 - Medicine & health
5
630 - Agriculture & related technologies
5
004 - Data processing & computer science
4
005 - Computer programming, programs & data
4
140 - Specific philosophical schools
4
340 - Law
4
532 - Fluid mechanics; liquid mechanics
4
533 - Gas mechanics
4
539 - Modern physics
4
550 - Earth sciences
4
553 - Economic geology
4
634 - Orchards, fruits & forestry
4
174 - Occupational ethics
3
570 - Life sciences; biology
3
572 - Biochemistry
3
631 - Techniques, equipment & materials
3
650 - Management & auxiliary services
3
710 - Civic & landscape art
3
003 - Systems
2
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