Classification
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510 - Mathematics
1
523 - Specific celestial bodies & phenomena
1
541 - Physical chemistry
1
570 - Life sciences; biology
1
571 - Physiology & related subjects
1
590 - Animals (Zoology)
1
600 - Technology
1
616 - Diseases
1
651 - Office services
1
660 - Chemical engineering
1
690 - Buildings
1
696 - Utilities
1
720 - Architecture
1