Classification
613 - Personal health & safety
614 - Incidence & prevention of disease
821
610 - Medicine & health
10
500 - Natural sciences & mathematics
5
331 - Labor economics
3
612 - Human physiology
3
330 - Economics
2
338 - Production
2
658 - General management
2
001 - Knowledge
1
140 - Specific philosophical schools
1
150 - Psychology
1
363 - Other social problems & services
1
364 - Criminology
1
380 - Commerce, communications & transportation
1
400 - Language
1
519 - Probabilities & applied mathematics
1
576 - Genetics & evolution
1
602 - Miscellany
1
900 - History & geography
1