Classification
910 - Geography & travel
71
330 - Economics
64
363 - Other social problems & services
36
551 - Geology, hydrology & meteorology
36
333 - Economics of land & energy
32
000 - Computer science, information & general works
29
700 - The arts; fine & decorative arts
29
519 - Probabilities & applied mathematics
26
304 - Factors affecting social behavior
25
600 - Technology
21
620 - Engineering & allied operations
19
900 - History & geography
18
577 - Ecology
16
005 - Computer programming, programs & data
15
610 - Medicine & health
15
006 - Special computer methods
14
500 - Natural sciences & mathematics
14
658 - General management
14
380 - Commerce, communications & transportation
12
140 - Specific philosophical schools
11
320 - Political science
11
580 - Plants (Botany)
10
004 - Data processing & computer science
8
576 - Genetics & evolution
8
300 - Social sciences
7
630 - Agriculture & related technologies
7
930 - History of ancient world to ca. 499
7
340 - Law
6
370 - Education
6
571 - Physiology & related subjects
6
001 - Knowledge
5
307 - Communities
5
414 - Phonology & phonetics
5
510 - Mathematics
5
550 - Earth sciences
5
614 - Incidence & prevention of disease
5
629 - Other branches of engineering
5
003 - Systems
4
570 - Life sciences; biology
4
616 - Diseases
4
621 - Applied physics
4
720 - Architecture
4
025 - Library operations
3
301 - Sociology & anthropology
3
306 - Culture & institutions
3
338 - Production
3
400 - Language
3
526 - Mathematical geography
3
572 - Biochemistry
3
581 - Specific topics in natural history
3
more ...