Classification
600 - Technology
108
540 - Chemistry & allied sciences
43
620 - Engineering & allied operations
31
330 - Economics
29
320 - Political science
25
700 - The arts; fine & decorative arts
25
900 - History & geography
24
333 - Economics of land & energy
13
660 - Chemical engineering
9
000 - Computer science, information & general works
8
576 - Genetics & evolution
8
580 - Plants (Botany)
8
669 - Metallurgy
8
363 - Other social problems & services
7
140 - Specific philosophical schools
5
500 - Natural sciences & mathematics
4
380 - Commerce, communications & transportation
3
414 - Phonology & phonetics
3
530 - Physics
3
547 - Organic chemistry
3
628 - Sanitary & municipal engineering
3
301 - Sociology & anthropology
2
420 - English & Old English
2
665 - Industrial oils, fats, waxes & gases
2
304 - Factors affecting social behavior
1
340 - Law
1
400 - Language
1
541 - Physical chemistry
1
546 - Inorganic chemistry
1
553 - Economic geology
1
610 - Medicine & health
1
621 - Applied physics
1
622 - Mining & related operations
1
661 - Industrial chemicals
1
668 - Technology of other organic products
1
671 - Metalworking & primary metal products
1
673 - Nonferrous metals
1
720 - Architecture
1
930 - History of ancient world to ca. 499
1