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DOS - Wikipedia
MS-DOS - Wikipedia
Department of State | Department of State
The Ultimate, Complete List of MS-DOS Commands - Lifewire
What is DOS (Disk Operating System)? - TechTarget
What Is DOS? - Codecademy
How to Use the Windows Command Line (DOS) - Computer Hope
How to run a DOS program in Windows 10 | PCWorld
How to Use DOS and the Windows Command Prompt - wikiHow
Microsoft DOS and Windows Command Line - Computer Hope