Bingham, Robert C. <br/><br/>
Economic concepts:  a programmed approach / 
Robert C. Bingham. 
 - 2nd ed. 
 - New York :  McGraw-Hill,   c1969 
 - 316 p. ;  26 cm. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Economics--Programmed instruction.