APA (7th ed.) Citation

Costales, B., Shapiro, G. N., & Aßmann, C. (2004). Sendmail 8.13 companion. O'Reilly.

Chicago Style (17th ed.) Citation

Costales, Bryan, Gregory Neil Shapiro, and Claus Aßmann. Sendmail 8.13 Companion. Beijing: O'Reilly, 2004.

MLA (9th ed.) Citation

Costales, Bryan, et al. Sendmail 8.13 Companion. O'Reilly, 2004.