APA (7th ed.) Citation

Hildebrandt, R., & Koetter, P. (2005). The book of Postfix: State-of-the-art message transport. No Starch Press.

Chicago Style (17th ed.) Citation

Hildebrandt, Ralf, and Patrick Koetter. The Book of Postfix: State-of-the-art Message Transport. San Francisco: No Starch Press, 2005.

MLA (8th ed.) Citation

Hildebrandt, Ralf, and Patrick Koetter. The Book of Postfix: State-of-the-art Message Transport. No Starch Press, 2005.