Classification
621 - Applied physics
250
620 - Engineering & allied operations
45
333 - Economics of land & energy
39
600 - Technology
28
629 - Other branches of engineering
22
900 - History & geography
17
700 - The arts; fine & decorative arts
16
321 - Systems of governments & states
9
338 - Production
9
380 - Commerce, communications & transportation
8
006 - Special computer methods
7
670 - Manufacturing
7
745 - Decorative arts
7
330 - Economics
6
624 - Civil engineering
6
658 - General management
6
000 - Computer science, information & general works
5
500 - Natural sciences & mathematics
4
576 - Genetics & evolution
3
580 - Plants (Botany)
3
610 - Medicine & health
3
720 - Architecture
3
005 - Computer programming, programs & data
2
530 - Physics
2
537 - Electricity & electronics
2
650 - Management & auxiliary services
2
004 - Data processing & computer science
1
140 - Specific philosophical schools
1
320 - Political science
1
350 - Public administration & military science
1
361 - Social problems & social welfare in general
1
363 - Other social problems & services
1
384 - Communications; telecommunication
1
509 - Historical, geographic & persons treatment
1
510 - Mathematics
1
515 - Analysis
1
519 - Probabilities & applied mathematics
1
531 - Classical mechanics; solid mechanics
1
539 - Modern physics
1
541 - Physical chemistry
1
546 - Inorganic chemistry
1
551 - Geology, hydrology & meteorology
1
571 - Physiology & related subjects
1
625 - Engineering of railroads & roads
1
627 - Hydraulic engineering
1
662 - Explosives, fuels & related products
1
696 - Utilities
1
786 - Keyboard & other instruments
1