Hass K B <br/><br/>
Preparation and use of audio visual aids 
Hass K B; Packer H Q 
 -  1950 
<br/><br/><label>Standard No.: </label>86,684 
<br/><br/><label>Source: </label> Textual 
<br/><br/><label>Subjects--Topical Terms: </label><br/>EDUCATION
<br/><br/><label>Dewey Class. No.: </label>T:31, J0