Classification
540 - Chemistry & allied sciences
3
700 - The arts; fine & decorative arts
2
000 - Computer science, information & general works
1
333 - Economics of land & energy
1
363 - Other social problems & services
1
523 - Specific celestial bodies & phenomena
1
541 - Physical chemistry
1
547 - Organic chemistry
1
572 - Biochemistry
1
620 - Engineering & allied operations
1
628 - Sanitary & municipal engineering
1
660 - Chemical engineering
1