@misc{indiciae9cae2a1d4534,
  title = {A revised version of Graphic Normative Analysis Program (GNAP) with examples of petrologic problem solving},
  author = {J. S. Stuckless and G. VanTrump},
  year = {1979},
  doi = {10.3133/ofr791237},
  url = {https://pubs.usgs.gov/publication/ofr791237},
  note = {Source identifier: ofr791237}
}