Freibergite Subgroup from
USA | |
| Rocks & Min.: 60:86. |
| (2005) Mineral Resources Data System (MRDS), US Geological Survey. |
| Christopher P.Indorf,1981,Economic Geology (v.76,p.1170)The Silver Hill zinc deposit and associated deposits,central North Carolina |
(2005) Mineral Resources Data System (MRDS), US Geological Survey. |