Merchant, Ronald <br/><br/>
Adding machines and calculators 

 - New York :  Wiley,  1973 
 - x, 182 p. :  ill. ;  26 cm. 
<br/><br/><label>ISBN: </label>047159444X 
<br/><br/><label>LCCN: </label>73-016107 //r86 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Calculators--Problems, exercises, etc