@misc{indiciae6d154dc7919f,
  title = {Geologic maps, cross section, and photographs of the central part of Glacier National Park, Montana},
  author = {R.L. Earhart and O. B. Raup and J. W. Whipple and A. L. Isom and G. A. Davis},
  year = {1989},
  doi = {10.3133/i1508b},
  url = {https://pubs.usgs.gov/publication/i1508B},
  note = {Source identifier: i1508B}
}