Classification
330 - Economics
333 - Economics of land & energy
363 - Other social problems & services
370 - Education
380 - Commerce, communications & transportation
600 - Technology
610 - Medicine & health
1
620 - Engineering & allied operations
1
658 - General management
1
700 - The arts; fine & decorative arts
1
800 - Literature & rhetoric
1
900 - History & geography
1