Classification
333 - Economics of land & energy
71
621 - Applied physics
65
600 - Technology
39
620 - Engineering & allied operations
38
330 - Economics
36
700 - The arts; fine & decorative arts
36
000 - Computer science, information & general works
26
900 - History & geography
22
580 - Plants (Botany)
16
363 - Other social problems & services
12
380 - Commerce, communications & transportation
11
551 - Geology, hydrology & meteorology
9
576 - Genetics & evolution
8
530 - Physics
7
540 - Chemistry & allied sciences
7
340 - Law
6
500 - Natural sciences & mathematics
6
800 - Literature & rhetoric
5
546 - Inorganic chemistry
4
630 - Agriculture & related technologies
4
304 - Factors affecting social behavior
3
320 - Political science
3
321 - Systems of governments & states
3
541 - Physical chemistry
3
628 - Sanitary & municipal engineering
3
658 - General management
3
720 - Architecture
3
338 - Production
2
610 - Medicine & health
2
660 - Chemical engineering
2
697 - Heating, ventilating & air-conditioning
2
370 - Education
1
414 - Phonology & phonetics
1
550 - Earth sciences
1
581 - Specific topics in natural history
1
657 - Accounting
1
662 - Explosives, fuels & related products
1
670 - Manufacturing
1
696 - Utilities
1