Burt, William Austin, 1792-1858, Houghton, Douglass, 1809-1845 (1845). 57N 32W - Survey Map of Sherman Township, Houghton Township, and Allouez Township, Keweenaw County [Michigan]. Department of Natural Resources. https://michigan.access.preservica.com/uncategorized/IO_ff662be3-7eb1-4e6c-8ed8-fe35225b3d7d (map)