TY  - RPRT
TI  - A method for development of a system of identification for Appalachian coal-bearing rocks
AU  - J.C. Ferm
AU  - G.A. Weisenfluh
AU  - G.C. Smith
PY  - 2002
DO  - 10.1016/s0166-5162(01)00072-6
UR  - https://pubs.usgs.gov/publication/70024829
ID  - 70024829
ER  -