Classification
551 - Geology, hydrology & meteorology
900 - History & geography
333 - Economics of land & energy
18
363 - Other social problems & services
17
600 - Technology
17
620 - Engineering & allied operations
13
700 - The arts; fine & decorative arts
13
330 - Economics
11
000 - Computer science, information & general works
9
380 - Commerce, communications & transportation
9
610 - Medicine & health
7
720 - Architecture
6
320 - Political science
5
370 - Education
4
140 - Specific philosophical schools
2
414 - Phonology & phonetics
2
500 - Natural sciences & mathematics
2
581 - Specific topics in natural history
2
170 - Ethics
1
530 - Physics
1
540 - Chemistry & allied sciences
1
576 - Genetics & evolution
1