00333nam a2200121Ia 4500008004100000020001500041100001700056245006200073260003400135300000800169650001600177650001800193170901s1974    xx            000 0 und d  a0387069542  aDuran, B. S. 0aLecture notes in economics & Mathematics system - Vol.100  aBerlinbSpringer-Verlagc1974  a137  aMathematics  aPure Sciences