Koff, Richard M. <br/><br/>
How does it work? / 
By Richard M. Koff ; Illus. by the author and Richard E. Rooman. 
 - New York :  Doubleday & Co.,  [1968]. 
 - 303 p. :  illus. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Implements, utensils, etc.<br/>Electric apparatus and appliances