bounded selfadjoint operator B to be normal is given. Various properties of the factors of the
unitary polar decompositions of A and B are obtained in the case when the product AB is
normal. A block operator model for pairs (A, B) of selfadjoint operators such that B is
bounded and AB is normal is established. The case when both operators A and B are
bounded is discussed. In addition, the example due to Rehder is reexamined from this point …