APA (7th ed.) Citation

(1988). Microsoft MS-DOS: User's reference : operating system version 4.0 ([1st ed.].). s. n.].

Chicago Style (17th ed.) Citation

Microsoft MS-DOS: User's Reference : Operating System Version 4.0. [1st ed.]. [S. l: s. n.], 1988.

MLA (9th ed.) Citation

Microsoft MS-DOS: User's Reference : Operating System Version 4.0. [1st ed.]. s. n.], 1988.