Classification
577 - Ecology
4
330 - Economics
2
520 - Astronomy & allied sciences
2
616 - Diseases
2
617 - Surgery & related medical specialties
2
620 - Engineering & allied operations
2
634 - Orchards, fruits & forestry
2
641 - Food & drink
2
664 - Food technology
2
001 - Knowledge
1
003 - Systems
1
005 - Computer programming, programs & data
1
153 - Mental processes & intelligence
1
158 - Applied psychology
1
300 - Social sciences
1
332 - Financial economics
1
333 - Economics of land & energy
1
338 - Production
1
361 - Social problems & social welfare in general
1
519 - Probabilities & applied mathematics
1
539 - Modern physics
1
549 - Mineralogy
1
551 - Geology, hydrology & meteorology
1
571 - Physiology & related subjects
1
612 - Human physiology
1
613 - Personal health & safety
1
621 - Applied physics
1
636 - Animal husbandry
1
910 - Geography & travel
1
941 - British Isles
1