Classification
540 - Chemistry & allied sciences
2,667
541 - Physical chemistry
1,977
620 - Engineering & allied operations
1,516
547 - Organic chemistry
1,386
660 - Chemical engineering
1,109
543 - Analytical chemistry
707
621 - Applied physics
630
615 - Pharmacology & therapeutics
624
546 - Inorganic chemistry
609
530 - Physics
599
577 - Ecology
579
572 - Biochemistry
551
363 - Other social problems & services
457
333 - Economics of land & energy
451
519 - Probabilities & applied mathematics
412
664 - Food technology
351
610 - Medicine & health
319
570 - Life sciences; biology
304
571 - Physiology & related subjects
293
600 - Technology
281
000 - Computer science, information & general works
266
700 - The arts; fine & decorative arts
259
641 - Food & drink
256
551 - Geology, hydrology & meteorology
237
628 - Sanitary & municipal engineering
186
580 - Plants (Botany)
182
500 - Natural sciences & mathematics
177
539 - Modern physics
171
616 - Diseases
158
670 - Manufacturing
136
630 - Agriculture & related technologies
131
330 - Economics
123
003 - Systems
122
629 - Other branches of engineering
118
536 - Heat
106
631 - Techniques, equipment & materials
79
581 - Specific topics in natural history
72
006 - Special computer methods
70
668 - Technology of other organic products
70
900 - History & geography
67
579 - Microorganisms, fungi & algae
66
542 - Techniques, equipment & materials
64
549 - Mineralogy
60
320 - Political science
59
612 - Human physiology
56
550 - Earth sciences
55
004 - Data processing & computer science
51
518 - Numerical analysis
50
576 - Genetics & evolution
48
531 - Classical mechanics; solid mechanics
47
more ...