000 00265nam a2200109Ia 4500
008 231212s1980 xx 000 0 und d
041 _aeng
082 _a621.384131
100 _aSavelyev I. V.
245 _aQuestions and Problems
260 _aMascow
_bMir Pub
_c1980
999 _c958460
_d958460