TY  - RPRT
TI  - Progressive regional metamorphism of the lower kittanning coal bed of western Pennsylvania
AU  - T. Stadnichenko
PY  - 1934
DO  - 10.2113/gsecongeo.29.6.511
UR  - https://pubs.usgs.gov/publication/70221659
ID  - 70221659
ER  -