Vatsya, S. Raj <br/><br/>
Foundations and applications of variational and perturbation methods / 
S. Raj Vatsya 
 - Hauppauge, NY :  Nova Science Publishers,,  2009 
 - viii, 337 p.;  26 cm. 
<br/><br/>Includes bibliographical references and index 
<br/><br/><label>ISBN: </label>9781606925911 (hardcover)  RM 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Perturbation (Mathematics)<br/>Perturbation (Quantum dynamics)<br/>Variational principles