Cita APA (7th ed.)
Willis, B. (1912). Index to the Stratigraphy of North America: Accompanied by a geologic map of North America. Compiled by .. Government Print. Office.
Cita Chicago (17th ed.)
Willis, Bailey. Index to the Stratigraphy of North America: Accompanied by a Geologic Map of North America. Compiled by .. Washington: Government Print. Office, 1912.
Cita MLA (9th ed.)
Willis, Bailey. Index to the Stratigraphy of North America: Accompanied by a Geologic Map of North America. Compiled by .. Government Print. Office, 1912.
Atenció: Aquestes cites poden no estar 100% correctes.