Walker, Arthur L. <br/><br/>
How to use adding and calculating machines :   ten-key, rotary, key -driven /  
Arthur L. Walker, J. Kenneth Roach and J. Marshall Hanna 
 - 2nd ed. 
 - New York :   McGraw-Hill,   1960 
 - 250 p. :    ill. ;    28 cm. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Calculators.--------
<br/><br/><label>Dewey Class. No.: </label>Q 651.264 WAL