Dufrénite from Black Hills, USA
USA | |
| Loomis, T. (2011), News from the Black Hills, South Dakota. Mineral News in press |
| Campbell, T.J., Roberts, W.L. (1985) Mineral Localities in the Black Hills of South Dakota. Rocks & Minerals: 60: 109-118 (117). |
| Loomis, T. (2011), News from the Black Hills, South Dakota. Mineral News in press |
| USGS Bull 380D |
| Rocks & Minerals: 67(6): 380-388. |
USGS Prof Paper 297B |