TY  - RPRT
TI  - Geologic map and cross section of the Abra Quadrangle, Costa Rica
AU  - Rolando M. Castillo
AU  - R.D. Krushensky
PY  - 1977
DO  - 10.3133/i992
UR  - https://pubs.usgs.gov/publication/i992
ID  - i992
ER  -