|
USA | |
| Ransom, Jay Ellis (1974) Gems and Minerals of America - A Guide to Rock Collecting. Harper & Row. |
| Cordua, William S. (1998) Wisconsin Mineral Locality Index. Rocks & Minerals, 73 (6) 378-399 doi:10.1080/00357529809603078 |
| [Agate var. Lake Superior Agate] Brian Cowger |
| Cordua, William S. (1998) Wisconsin Mineral Locality Index. Rocks & Minerals, 73 (6) 378-399 doi:10.1080/00357529809603078 |
| Cordua, William S. (1998) Wisconsin Mineral Locality Index. Rocks & Minerals, 73 (6) 378-399 doi:10.1080/00357529809603078 |
| Leighton, M. W. (1954) Petrogenesis of a gabbro - granophyre complex in northern Wisconsin" Geological Society of America Bulletin: 65: 401-442. |
| Cordua, William S. (1998) Wisconsin Mineral Locality Index. Rocks & Minerals, 73 (6) 378-399 doi:10.1080/00357529809603078 |