@misc{indiciaed20c57115405,
  title = {Archean geology of the northern block of the Ishpeming greenstone belt, Marquette County, Michigan},
  author = {R. C. Johnson and T.J. Bornhorst and L. M. H. Carter},
  year = {1991},
  doi = {10.3133/b1904f},
  url = {https://pubs.usgs.gov/publication/b1904F},
  note = {Source identifier: b1904F}
}