APA (7th ed.) Citation

Costales, B., & Allman, E. (1993). Sendmail. O'Reilly & Associates, Inc.

Chicago Style (17th ed.) Citation

Costales, Bryan, and Eric Allman. Sendmail. Sebastopol, Calif: O'Reilly & Associates, Inc, 1993.

MLA (9th ed.) Citation

Costales, Bryan, and Eric Allman. Sendmail. O'Reilly & Associates, Inc, 1993.