000 00295nam a2200121Ia 4500
008 191031s9999 xx 000 0 und d
100 _aElsgolts (L)
245 0 _aDifferntial equations and the calculus of variations
260 _bMir publish
260 _c1980
365 _b10
942 _cBK
999 _c209174
_d209174