TY  - RPRT
TI  - Metalliferous black shales and related ore deposits; program and abstracts
AU  - Richard I. Grauch
AU  - Joel S. Leventhal
PY  - 1989
DO  - 10.3133/cir1037
UR  - https://pubs.usgs.gov/publication/cir1037
ID  - cir1037
ER  -