Aspects of educational technology / 
edited for the Association for Programmed Learning and EducationalTechnology by Lionel Evans and John Leedham 
 - London :  Pitman Pub.,  1975 
 - v. ;  25 cm. 
<br/><br/><label>ISBN: </label>0273317830 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Educational technology