Nikolski N.K. <br/><br/>
Operators, Functions and Systems: An Easy reading. V.2:Model Operators and Systems 
Nikolski N.K. 
 - Providence  American Mathematical Society  2002 
 - 439 p. 
<br/><br/> Mathematical Surveys and Monographs V.92 
<br/><br/><label>Dewey Class. No.: </label>517.982