Bellman, Richard Ernest, <br/><br/>
Perturbation Techniques in mathematics, engineering and physics 
 Peturbation techniques in mathematics, engineering &​ physics.  Peturbation techniques. 

 - New york:  Dover Publication,  1966. 
 - viii, 118 p.:   ill. ;  22 cm. 
<br/><br/> Originally published: New York : Holt, Rinehart and Winston, c1964 in series: Athena series; selected topics in mathematics.  
<br/><br/><label>ISBN: </label>9780486432588 
<br/><br/><label>Dewey Class. No.: </label>515.35 BEL