000 00280nam a2200109Ia 4500
001 81028
008 170722s9999 xx 000 0 und d
245 _aMathematical models in educational planning /
260 _aparic :
_bO E C D ,
_c1967.
300 _a296 p.
_c27cms
942 _cGEN
999 _c93158
_d93158