Classification
507 - Education, research & related topics
43
530 - Physics
17
370 - Education
13
500 - Natural sciences & mathematics
9
621 - Applied physics
9
510 - Mathematics
7
540 - Chemistry & allied sciences
7
371 - Schools & their activities; special education
6
531 - Classical mechanics; solid mechanics
6
570 - Life sciences; biology
5
541 - Physical chemistry
4
650 - Management & auxiliary services
4
378 - Higher education
3
532 - Fluid mechanics; liquid mechanics
3
533 - Gas mechanics
3
572 - Biochemistry
3
300 - Social sciences
2
305 - Social groups
2
306 - Culture & institutions
2
512 - Algebra
2
515 - Analysis
2
612 - Human physiology
2
620 - Engineering & allied operations
2
910 - Geography & travel
2
001 - Knowledge
1
301 - Sociology & anthropology
1
302 - Social interaction
1
304 - Factors affecting social behavior
1
330 - Economics
1
374 - Adult education
1
407 - Education, research & related topics
1
516 - Geometry
1
519 - Probabilities & applied mathematics
1
520 - Astronomy & allied sciences
1
534 - Sound & related vibrations
1
539 - Modern physics
1
543 - Analytical chemistry
1
547 - Organic chemistry
1
551 - Geology, hydrology & meteorology
1
571 - Physiology & related subjects
1
579 - Microorganisms, fungi & algae
1
580 - Plants (Botany)
1
600 - Technology
1