Gaya APA

Northrop, S, A. (1939). Paleontology and Stratigraphy of the Silurian Rocks of the Port Daniel-Black Cappe Region, Gaspe . United States of America: The Society.

Gaya MLA

Northrop, Stuart,, Alvord.. "Paleontology and Stratigraphy of the Silurian Rocks of the Port Daniel-Black Cappe Region, Gaspe". United States of America: The Society, 1939. Text.