Cita APA (7a ed.)

Schwartz, A., & Garfinkel, S. (1998). Stopping spam. O'Reilly.

Cita Chicago Style (17a ed.)

Schwartz, Alan, y Simson Garfinkel. Stopping Spam. Sebastopol, California: O'Reilly, 1998.

Cita MLA (9a ed.)

Schwartz, Alan, y Simson Garfinkel. Stopping Spam. O'Reilly, 1998.