000 00246nam a2200085Ia 4500
001 MPKV108564
008 120911s9999 xx 000 0 und d
245 _aEconometrica. Vol.55 Part.1-3
_c;
260 _aIllinois.
_bUniversity of Chicago Chicago.
_c1987
999 _c71919
_d71919