@misc{indiciae4a88d9622e7a,
  title = {Bedrock geologic map of the Port Wing, Solon Springs, and parts of the Duluth and Sandstone 30' x 60' quadrangles, Wisconsin and Minnesota},
  author = {Suzanne W. Nicholson and William F. Cannon and Laurel G. Woodruff and Connie L. Dicken},
  year = {2006},
  doi = {10.3133/sim2869},
  url = {https://pubs.usgs.gov/publication/sim2869},
  note = {Source identifier: sim2869}
}