Cita APA (7a ed.)

Kaplan, J. (1966). Mr Clemens and Mark Twain. Penguin.

Cita Chicago Style (17a ed.)

Kaplan, Justin. Mr Clemens and Mark Twain. Middlesex: Penguin, 1966.

Cita MLA (9a ed.)

Kaplan, Justin. Mr Clemens and Mark Twain. Penguin, 1966.