Drooyan, Irving <br/><br/>
Essentials of trigonometry 
Irving Drooyan, Walter Hadel, Charles C. Carico 
 - 3d ed 
 - New York  Macmillan  1981 
 - 328p. 23cm 
<br/><br/> Includes index  'A portion of this material has been adapted from Trigonometry: an analytical approach.' 
<br/><br/><label>ISBN: </label>0023302704 
<br/><br/><label>LCCN: </label>79-22994 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Trigonometry, Plane