TY  - RPRT
TI  - Ordovician and Silurian graptolite succession in the Trail Creek area, central Idaho; a graptolite zone reference section
AU  - Claire Carter
AU  - Michael Churkin
PY  - 1977
DO  - 10.3133/pp1020
UR  - https://pubs.usgs.gov/publication/pp1020
ID  - pp1020
ER  -