Best, Gerald <br/><br/>
Biological studies river  [kit] / 
by Dr. Gerald Best 
 - New York :  Focal Point Audio Visual Ltd.,  1980 
 - 51 slides, 1 sound cassette, 1 note ;  in container, 29 X 27 X 8 cm. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Pollution--Study and teaching