000 00266nam a2200121Ia 4500
008 211209s1975 xx 000 0 und d
041 _aeng
082 _a510 N75 NOR
100 _aNORTHROP E P
245 _aRIDDLES IN MATHEMATICS
260 _c1975
300 _a240
999 _c14624
_d14624