The national audio-visual aids service. 

 - London :    Educational Foundation for Visual Aids,    [n.d.]. 
 - 8 p. :    ill. ;    22 cm. 
<br/><br/><label>Subjects--Topical Terms: </label><br/> Audio-visual materials.<br/> Visual education.<br/> Motion pictures.
<br/><br/><label>Dewey Class. No.: </label>371.33