proposition: Lemma indic_fubini_tonelli2 : \int[m1 \x^ m2]_z (f z)%:E = \int[m2]_y G y.
proof: Proof. by rewrite /f integral_indic// setIT indic_fubini_tonelli_GE. Qed.
imports: HB(structures) mathcomp(all_ssreflect ssralg ssrnum ssrint interval finmap) mathcomp(mathcomp_extra boolp classical_sets functions) mathcomp(cardinality fsbigop ) signed reals ereal topology normedtype sequences real_interval esum measure lebesgue_measure numfun