Microsoft MS-Dos. 

 - Condensed ed. 
 - Redmond :  Phoenix computer products,  c1988. 
 - 222 p. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Operating systems (Computers)
<br/><br/><label>LC Class. No.: </label>QA76.76  / .O63  / M53