TY  - RPRT
TI  - Coking coal of the United States—Modern and historical coking coal mining locations and chemical, rheological, petrographic, and other data from modern samples
AU  - Michael H. Trippi
AU  - Leslie F. Ruppert
AU  - Cortland F. Eble
AU  - James C. Hower
PY  - 2021
DO  - 10.3133/ofr20201113
UR  - https://pubs.usgs.gov/publication/ofr20201113
ID  - ofr20201113
ER  -