Operations and maintenance manual. 

 - Washington, D.C. :    United States Environmental Protection Agency,    1990. 
 - v. :    ill. ;    28 cm. 
<br/><br/>  21M-1010 
<br/><br/><label>Subjects--Topical Terms: </label><br/> Information technology -- Manuals.
<br/><br/><label>Dewey Class. No.: </label>005.43