APA (7th ed.) Citation

Swain, L., & Tallim, P. (1990). X.400: The Standard for Message Handling Systems.

Chicago Style (17th ed.) Citation

Swain, Leigh, and Paula Tallim. X.400: The Standard for Message Handling Systems. 1990.

MLA (9th ed.) Citation

Swain, Leigh, and Paula Tallim. X.400: The Standard for Message Handling Systems. 1990.

Warning: These citations may not always be 100% accurate.