1. Investigation of the Failure of Roofs in Coal Mines;Aughenbaugh,1973
2. Humidity Effects on Coal Mine Roof Stability;Aughenbaugh;Bureau of Mines Final Report,1976
3. Oxidation of pyritic sulfur in coal mines;Burke;Trans. AIME,1938
4. Shale alteration by water absorption;Chenevert Martin;J. Petrol. Technol.,1970
5. Analysis of Physical Properties of Coal Measure Rocks;Chugh,1977