Economic analysis of pressing social problem 
/ ed. by Llad Phillips, Harold L. Votey 
. - 2nd ed. 
. - Chicago  : McNally College, 1977
. - 390 p.  ; 23 cm. 
<br/><br/><label>Source: </label>89997  Fonds S.400 
<br/><br/><label>Universal Decimal Class. No.: </label>330.