Sandstone from Custer County, South Dakota, USA
USA | |
| (2005) Mineral Resources Data System (MRDS), US Geological Survey. |
| (2005) Mineral Resources Data System (MRDS), US Geological Survey. |
(2005) Mineral Resources Data System (MRDS), US Geological Survey. | |
(2005) Mineral Resources Data System (MRDS), US Geological Survey. | |
| KellerLynn, K. (2009) Wind Cave National Park Geologic Resources Inventory Report. Natural |