Wittich Walter Arno <br/><br/>
Audio-visual materials: Their nature and use 

 - New York, USA  Harper and Brothers Publisher  1953 
 - xx,564p 
 - Exploration Series in Education .
<br/><br/><label>Source: </label>TextBook 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Teaching Aids; Audio -Visual Materials