00269cam a2200109ua 4500041001000000082001800010100003000028245004200058260004200100300001200142504000500154  aengh  a330.1bJAT/El  aG.B. Jathar, S.G. Beli  .  aElementary priciples of ecomnomics``   a : bOxfor university press , c1961.  a424 ; .  a