Jorgens, K & Weidmann, J <br/><br/>
Spectral properties of hamiltonian operators 
K. Jorgens & J. Weidmann 
 - Berlin  Springer  1973 
 - 140 
 - Lecture notes in mathematics 313 .
<br/><br/><label>ISBN: </label>3540061517 
<br/><br/><label>Dewey Class. No.: </label>12.05  / 22 JORG