Classification
630 - Agriculture & related technologies
29
551 - Geology, hydrology & meteorology
9
577 - Ecology
9
333 - Economics of land & energy
8
910 - Geography & travel
4
579 - Microorganisms, fungi & algae
3
580 - Plants (Botany)
3
628 - Sanitary & municipal engineering
3
660 - Chemical engineering
3
338 - Production
2
550 - Earth sciences
2
613 - Personal health & safety
2
624 - Civil engineering
2
641 - Food & drink
2
664 - Food technology
2
363 - Other social problems & services
1
500 - Natural sciences & mathematics
1
519 - Probabilities & applied mathematics
1
520 - Astronomy & allied sciences
1
526 - Mathematical geography
1
530 - Physics
1
571 - Physiology & related subjects
1
590 - Animals (Zoology)
1
604 - Special topics
1
634 - Orchards, fruits & forestry
1
690 - Buildings
1