TY  - RPRT
TI  - A revised version of Graphic Normative Analysis Program (GNAP) with examples of petrologic problem solving
AU  - J. S. Stuckless
AU  - G. VanTrump
PY  - 1979
DO  - 10.3133/ofr791237
UR  - https://pubs.usgs.gov/publication/ofr791237
ID  - ofr791237
ER  -