SPIEGEL, Murray R. <br/><br/>
Theory And Problems Of Calculus Of Finite Differences And Differences Equations 

 - New York,  Mcgraw Hill Book Company,  1971 
 - 253p. 
<br/><br/><label>ISBN: </label>70602182 
<br/><br/><label>Dewey Class. No.: </label>515.38