TY  - RPRT
TI  - Determination of ash in coals unusually high in calcite and pyrite
AU  - O.W. Rees
AU  - W.A. Selvig
PY  - 2002
DO  - 10.1021/i560103a006
UR  - https://pubs.usgs.gov/publication/70010996
ID  - 70010996
ER  -