@misc{indiciaed853035493eb,
  title = {Transcontinental geophysical survey (35° - 39° N) geologic map from the East Coast of the United States to 87° W longitude},
  author = {Ronald Willden and J. C. Reed and J. E. Carlson},
  year = {1968},
  doi = {10.3133/i535c},
  url = {https://pubs.usgs.gov/publication/i535C},
  note = {Source identifier: i535C}
}