Gagne,Robert M. <br/><br/>
Princeples of instructional design. 

 - 2nd  ed. 
 - New york :  Holt,  1974. 
 - 321  p. ;    cm. 
<br/><br/>index. 
<br/><br/><label>ISBN: </label> $ 
<br/><br/><label>Subjects--Topical Terms: </label><br/>learning psychology.