Asymptotic solutions of the one-dimensional Schrödinger equation 
Slavi︠a︡nov, S. I︠U︡. 
 - Providence, R.I. :  American Mathematical Society,  1996 
 - xvi, 190 p. :  ill. ;  27 cm. 
 - Translations of mathematical monographs,  v. 151 .
<br/><br/><label>ISBN: </label>0821805363 (acid-free paper)