TY  - RPRT
TI  - USGS Permo-Carboniferous fossil locality register; Part 1, Introduction to PC-FILES
AU  - T. W. Henry
AU  - O.B. Williams
AU  - P.A. Holroyd
PY  - 1993
DO  - 10.3133/ofr93513
UR  - https://pubs.usgs.gov/publication/ofr93513
ID  - ofr93513
ER  -