@misc{indiciae0b9f41b8a8af,
  title = {GSDRAW and GSMAP version 4.0; prototype programs for the IBM PC and compatible microcomputers to assist compilation and publication of geologic maps and illustrations; D, Executable utility program disks},
  author = {Gary I. Selner and Richard B. Taylor},
  year = {1987},
  doi = {10.3133/ofr87496d},
  url = {https://pubs.usgs.gov/publication/ofr87496D},
  note = {Source identifier: ofr87496D}
}