@misc{indiciae54e5a64fe673,
  title = {GSMDATUM and GSPDATUM, programs for DOS microcomputers to convert data in GSMAP or GSPOST format between the NAD27 and NAD 83 coordinate systems},
  author = {G.I. Selner and R. B. Taylor},
  year = {1993},
  doi = {10.3133/ofr93536},
  url = {https://pubs.usgs.gov/publication/ofr93536},
  note = {Source identifier: ofr93536}
}