Não informado. (1931). Mineralogist. Oregon Agate and Mineral Society.
Chicago (17e ed.) BronvermeldingNão informado. Mineralogist. Portland, Ore: Oregon Agate and Mineral Society, 1931.
MLA (8e ed.) BronvermeldingNão informado. Mineralogist. Oregon Agate and Mineral Society, 1931.
Let op: Deze citaties zijn niet altijd 100% accuraat.