Não informado. (2000). Technical papers. U.S. Department of the Interior, Bureau of Mines.
Chicago-Zitierstil (17. Ausg.)Não informado. Technical Papers. Washington: U.S. Department of the Interior, Bureau of Mines, 2000.
MLA-Zitierstil (8. Ausg.)Não informado. Technical Papers. U.S. Department of the Interior, Bureau of Mines, 2000.
Achtung: Diese Zitate sind unter Umständen nicht zu 100% korrekt.