Não informado. (2009). Mines and Mineral Statistics. Commissioner of Mineral Statistics of the State of Michigan.
Chicago-Zitierstil (17. Ausg.)Não informado. Mines and Mineral Statistics. Lansing, Mich: Commissioner of Mineral Statistics of the State of Michigan, 2009.
MLA-Zitierstil (8. Ausg.)Não informado. Mines and Mineral Statistics. Commissioner of Mineral Statistics of the State of Michigan, 2009.
Achtung: Diese Zitate sind unter Umständen nicht zu 100% korrekt.