Checkland, Peter. <br/><br/>
Soft systems methodology :  a 30 year retrospective / 
Peter Checkland. 
 - Repr.February 2009. 
 - Chichester [etc.] :  John Wiley&Sons,  cop. 2009. 
 - A 66, XIV, 330 s. :  il. ;  23 cm. 
<br/><br/>Bibliogr. s.299-311. Indeks. 
<br/><br/><label>ISBN: </label>9780471986065