|
USA | |
| William S. Cordua |
| Cordua, W.S., 1998, "Minerals of Wisconsin", Rocks and Minerals vol. 73 #6, p. 378 - 398. |
| Heyl, A. & W. West, 1982, Outlying mineral occurrences related to the Upper Mississippi Valley Mineral District, Wisconsin, Iowa, Illinois, and Minnesota, Economic Geology: 77(8):1803-1817. |