APA (7th ed.) Citation

Harte, B. (1871). The Pliocene skull. [publisher not identified].

Chicago Style (17th ed.) Citation

Harte, Bret. The Pliocene Skull. [Washington, D.C.]: [publisher not identified], 1871.

MLA (9th ed.) Citation

Harte, Bret. The Pliocene Skull. [publisher not identified], 1871.