Guide to microreproduction equipment / 
edited by H.W. Ballou. 
 - 4th ed. 
 - Silver Spring, Md. :  National Microform Association,  1970 
 - 247 p. :  ill. ;  23 cm. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Microphotography--Apparatus and supplies--Periodicals<br/>Photocopying processes--Periodicals