- Author
- Diamond, W. P. | Oyler, D. C. | Fields, H. H.
- Title
- Directionally Controlled Drilling to Horizontally Intercept Selected Strata, Upper Freeport Coalbed, Greene County, PA.
- Coporate
- Bureau of Mines, Pittsburgh, PA
- Report
- RI 8231, 1977, 24 p.
- Keywords
- mine gases | mine ventilation | coal mines
- Identifiers
- boring