Topic
- Teachers3
- Tourism3
- Unemployment3
- United States Constitution Bicentennial, 1987-19913
- 4-H clubs2
- Airlines2
- Coal mines and mining2
- Construction2
- Discrimination in employment2
- Energy conservation2
- Environmental protection2
- Local transit2
- Lungs--Dust diseases2
- Petroleum industry and trade--United States2
- Pollution2
- Radioactive wastes2
- Reclamation of land--United States2
- Scholarships2
- Sewage disposal plants2
- Strip mining2
