Costales, B., & Allman, E. (1997). Sendmail (Second revised and updated edition.). O'Reilly; Shroff Publishers & Distributors PVT.LTD..
Chicago (17e ed.) BronvermeldingCostales, Bryan, en Eric Allman. Sendmail. Second revised and updated edition. Beijing ; Sebastopol, CA : Mumbai ; Calcutta: O'Reilly; Shroff Publishers & Distributors PVT.LTD., 1997.
MLA (8e ed.) BronvermeldingCostales, Bryan, en Eric Allman. Sendmail. Second revised and updated edition. O'Reilly; Shroff Publishers & Distributors PVT.LTD., 1997.
Let op: Deze citaties zijn niet altijd 100% accuraat.