Não informado. (2000). Technical papers. U.S. Department of the Interior, Bureau of Mines.
Chicago (17e ed.) BronvermeldingNão informado. Technical Papers. Washington: U.S. Department of the Interior, Bureau of Mines, 2000.
MLA (8e ed.) BronvermeldingNão informado. Technical Papers. U.S. Department of the Interior, Bureau of Mines, 2000.
Let op: Deze citaties zijn niet altijd 100% accuraat.