Classification
501 - Philosophy & theory
332
900 - History & geography
297
509 - Historical, geographic & persons treatment
287
510 - Mathematics
114
520 - Astronomy & allied sciences
114
530 - Physics
95
100 - Philosophy & psychology
83
500 - Natural sciences & mathematics
82
300 - Social sciences
68
610 - Medicine & health
57
600 - Technology
50
620 - Engineering & allied operations
48
621 - Applied physics
40
306 - Culture & institutions
36
320 - Political science
36
540 - Chemistry & allied sciences
36
301 - Sociology & anthropology
33
800 - Literature & rhetoric
32
576 - Genetics & evolution
31
700 - The arts; fine & decorative arts
30
570 - Life sciences; biology
29
109 - Historical & collected persons treatment
27
330 - Economics
26
200 - Religion
24
140 - Specific philosophical schools
23
120 - Epistemology, causation & humankind
22
370 - Education
21
551 - Geology, hydrology & meteorology
21
612 - Human physiology
20
001 - Knowledge
19
333 - Economics of land & energy
19
004 - Data processing & computer science
18
616 - Diseases
18
304 - Factors affecting social behavior
17
344 - Labor, social, education & cultural law
17
363 - Other social problems & services
17
629 - Other branches of engineering
17
809 - History, description & criticism
16
170 - Ethics
14
190 - Modern western philosophy
13
303 - Social processes
13
338 - Production
13
507 - Education, research & related topics
13
519 - Probabilities & applied mathematics
13
940 - History of Europe
13
150 - Psychology
12
410 - Linguistics
12
539 - Modern physics
12
550 - Earth sciences
11
571 - Physiology & related subjects
11
more ...