Our proof is obtained by the regularity properties of the corresponding regular Borel measure on [??] and is very different from the given in [3] and other known proofs.
Considering [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII], we shall get an E-valued regular Borel measure [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII] ([7]) (we denote the measure j by the same notation as operator [??] because the operator [??] uniquely extends to all [??]-integrable functions).
In this case we prove that any Baire measure can be uniquely extended to regular Borel measure.