@misc{indiciaeb50802853eb6,
  title = {Tectonic imbrication and foredeep development in the Penokean orogen, east-central Minnesota: An interpretation based on regional geophysics and the results of test-drilling. The Penokean orogeny in Minnesota and upper Michigan; a comparison of structural geology},
  author = {D. L. Southwick and G. B. Morey and Timothy B. Holst and L. M. H. Carter},
  year = {1991},
  doi = {10.3133/b1904cd},
  url = {https://pubs.usgs.gov/publication/b1904CD},
  note = {Source identifier: b1904CD}
}