00260nam a2200109Ia 4500082001800000100002300018245004500041260003400086300002000120500000500140700000500145  a339bSc344.IA  aSchlieht, Ekkehart  aIsolation and aggregation in economicsb  aBerlinbSpringer Verlagc1985  axi, 110p. Index  a  a