Classification
621 - Applied physics
417
620 - Engineering & allied operations
396
536 - Heat
248
530 - Physics
216
333 - Economics of land & energy
120
000 - Computer science, information & general works
85
700 - The arts; fine & decorative arts
80
600 - Technology
75
541 - Physical chemistry
73
531 - Classical mechanics; solid mechanics
63
660 - Chemical engineering
60
629 - Other branches of engineering
46
900 - History & geography
35
540 - Chemistry & allied sciences
33
330 - Economics
28
363 - Other social problems & services
27
500 - Natural sciences & mathematics
27
576 - Genetics & evolution
25
551 - Geology, hydrology & meteorology
24
539 - Modern physics
20
515 - Analysis
19
580 - Plants (Botany)
19
610 - Medicine & health
19
006 - Special computer methods
16
340 - Law
15
380 - Commerce, communications & transportation
15
519 - Probabilities & applied mathematics
15
546 - Inorganic chemistry
13
547 - Organic chemistry
13
140 - Specific philosophical schools
12
670 - Manufacturing
12
550 - Earth sciences
10
628 - Sanitary & municipal engineering
9
720 - Architecture
9
003 - Systems
8
662 - Explosives, fuels & related products
8
668 - Technology of other organic products
8
690 - Buildings
8
696 - Utilities
8
572 - Biochemistry
7
697 - Heating, ventilating & air-conditioning
6
414 - Phonology & phonetics
5
537 - Electricity & electronics
5
548 - Crystallography
5
571 - Physiology & related subjects
5
624 - Civil engineering
5
661 - Industrial chemicals
5
338 - Production
4
523 - Specific celestial bodies & phenomena
4
526 - Mathematical geography
4
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