Classification
600 - Technology
620 - Engineering & allied operations
28
005 - Computer programming, programs & data
27
900 - History & geography
17
000 - Computer science, information & general works
15
333 - Economics of land & energy
12
700 - The arts; fine & decorative arts
12
330 - Economics
11
331 - Labor economics
9
370 - Education
9
363 - Other social problems & services
8
658 - General management
8
004 - Data processing & computer science
4
340 - Law
4
380 - Commerce, communications & transportation
4
610 - Medicine & health
4
629 - Other branches of engineering
4
500 - Natural sciences & mathematics
3
580 - Plants (Botany)
3
100 - Philosophy & psychology
2
140 - Specific philosophical schools
2
304 - Factors affecting social behavior
2
360 - Social problems & services; associations
2
361 - Social problems & social welfare in general
2
540 - Chemistry & allied sciences
2
576 - Genetics & evolution
2
745 - Decorative arts
2
006 - Special computer methods
1
200 - Religion
1
300 - Social sciences
1
301 - Sociology & anthropology
1
384 - Communications; telecommunication
1
530 - Physics
1
551 - Geology, hydrology & meteorology
1
581 - Specific topics in natural history
1
621 - Applied physics
1
630 - Agriculture & related technologies
1
643 - Housing & household equipment
1
670 - Manufacturing
1