@misc{indiciae04cbed9f4f33,
  title = {Geologic map of the El Portal Quadrangle, west-central Sierra Nevada, California},
  author = {P. C. Bateman and K.B. Krauskopf},
  year = {1987},
  doi = {10.3133/mf1998},
  url = {https://pubs.usgs.gov/publication/mf1998},
  note = {Source identifier: mf1998}
}