1. Principal coal beds in the Troublesome quadrangle, Breathitt, Knott, and Perry Counties, Kentucky
1953. 2018-06-21T19:42:46Z. 2018-06-21T19:42:46Z. Williamson, A. D. The Survey. English. cartographic image. Public. Kentucky, Knott County, Breathitt County, Perry County, Breathitt County., Knott County., and Perry County.
