Valkenburg, M. E. Van. <br/><br/>
Network analysis / 
M. E. Van Valkenburg. 
 - 10th ed. 
 - [S.l.] :  TBS,  1974. 
 - 592 p. 
<br/><br/><label>ISBN: </label>8120301560 (paperback) 9788120301566 (paperback)