APA

Hay O. P., . (1923). The pleistocene of North America and its vertebrated animals from the states east of the Mississippi River and from the Canadian. Washington: Carnegie Institution.

Chicago

Hay Oliver P, . 1923. The pleistocene of North America and its vertebrated animals from the states east of the Mississippi River and from the Canadian. Washington: Carnegie Institution.

Harvard

Hay O. P., . (1923). The pleistocene of North America and its vertebrated animals from the states east of the Mississippi River and from the Canadian. Washington: Carnegie Institution.

MLA

Hay Oliver P, . The pleistocene of North America and its vertebrated animals from the states east of the Mississippi River and from the Canadian. Washington: Carnegie Institution. 1923.