Cita APA (7th ed.)

British Museum (Natural History). Dept. of Mineralogy & Smith, W. C. (1949). Guide to the collection of rocks (2nd ed.). Printed by order of the Trustees of the British Museum.

Cita Chicago (17th ed.)

British Museum (Natural History). Dept. of Mineralogy i Walter Campbell Smith. Guide to the Collection of Rocks. 2nd ed. London: Printed by order of the Trustees of the British Museum, 1949.

Cita MLA (8th ed.)

British Museum (Natural History). Dept. of Mineralogy i Walter Campbell Smith. Guide to the Collection of Rocks. 2nd ed. Printed by order of the Trustees of the British Museum, 1949.