Classification
620 - Engineering & allied operations
11
330 - Economics
9
512 - Algebra
6
616 - Diseases
6
658 - General management
5
300 - Social sciences
4
301 - Sociology & anthropology
4
306 - Culture & institutions
4
519 - Probabilities & applied mathematics
4
530 - Physics
4
700 - The arts; fine & decorative arts
4
142 - Critical philosophy
3
380 - Commerce, communications & transportation
3
551 - Geology, hydrology & meteorology
3
610 - Medicine & health
3
004 - Data processing & computer science
2
305 - Social groups
2
320 - Political science
2
333 - Economics of land & energy
2
338 - Production
2
515 - Analysis
2
520 - Astronomy & allied sciences
2
531 - Classical mechanics; solid mechanics
2
571 - Physiology & related subjects
2
617 - Surgery & related medical specialties
2
621 - Applied physics
2
704 - Special topics in fine & decorative arts
2
809 - History, description & criticism
2
003 - Systems
1
005 - Computer programming, programs & data
1
050 - General serial publications
1
100 - Philosophy & psychology
1
128 - Humankind
1
152 - Perception, movement, emotions & drives
1
297 - Islam, Babism & Bahai Faith
1
302 - Social interaction
1
325 - International migration & colonization
1
332 - Financial economics
1
336 - Public finance
1
363 - Other social problems & services
1
370 - Education
1
374 - Adult education
1
384 - Communications; telecommunication
1
404 - Special topics
1
418 - Standard usage & applied linguistics
1
507 - Education, research & related topics
1
510 - Mathematics
1
516 - Geometry
1
532 - Fluid mechanics; liquid mechanics
1
533 - Gas mechanics
1
more ...