@misc{indiciae06424a62cdb5,
  title = {Bedrock geologic map of the Greenwood quadrangle, Marquette County, Michigan},
  author = {William F. Cannon},
  year = {1974},
  doi = {10.3133/gq1168},
  url = {https://pubs.usgs.gov/publication/gq1168},
  note = {Source identifier: gq1168}
}