Boundary value problems and symplectic algebra for ordinary differential and quasi-differential operators  
Everitt, W. N. 
 - Providence, R.I. :  American Mathematical Society,  1999 
 - 1 online resource (xii, 187 p. : ill.) 
<br/><br/><label>ISBN: </label>0821810804 | 9781470412883 (online)