5Harpalani S, Schraufnagel R A. Shrinkage of coal matrix with release of gas and its impact on permeability of coal [J]. Fuel, 1991, 69 (5): 551-556.
6Harpalani S. The effect of gas evacation on coal permeability test specimens [ J]. Int. J. Rock Mech. Sci. & Geomech. , 1984, 21 (3): 361 -364.
7Dabbous M K. The permeability of coal to gas and water [J]. SPEJ, 1974:563 -572.
8Schwerer F C, Pavone A M. Effect of pressure dependent permeability on well test analyses and long term production of methane from coal seams [R]. SPE12857, 1984.
9Roberts S B, Stanton R W, Flores R M. A debris flow deposit in alluvial, coal-bearing faces, Bighorn Basin, Wyoming, USA: evidence for catatrophic termination of a mire [ J]. International Journal of Coal Geology, 1994 (25) : 213 -241.