APA (7e ed.) Bronvermelding

Não informado. (1926). Rocks and Minerals. Heldref Publications.

Chicago (17e ed.) Bronvermelding

Não informado. Rocks and Minerals. Washington: Heldref Publications, 1926.

MLA (8e ed.) Bronvermelding

Não informado. Rocks and Minerals. Heldref Publications, 1926.

Let op: Deze citaties zijn niet altijd 100% accuraat.