Pólya George  18871985 <br/><br/>
How to solve it;   a new aspect of mathematical method 

 - 2d ed. 
 - Garden City, N.Y.,   Doubleday,   1957. 
 - 253 p.   18 cm. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Mathematics--Study and teaching
<br/><br/><label>LC Class. No.: </label>QA11