Cite
Boerboom, Terrence J., Chandler, Val W., Jirsa, Mark A., McSwiggen, Peter L.. (1991). Bedrock geology of the Cook-Side Lake area, St Louis and Itasca Counties, Minnesota, M-75. Minnesota Geological Survey. https://reflections.mndigital.org/catalog/mgs:1167 (map)
Available from: https://geo.btaa.org/catalog/2db06ebf-7551-4cb7-842d-9c65644e7430