“…The factorization has been applied in scientific computing -especially in science and engineering -see also [10,19,21,25,39]. Other variations of W Z factorization are detailed in [15,20,23,36,38], but block W Z factorization (or its Z system ) is discussed in [7,9,26]. The newest and alternative form of W Z factorization with applications is the W H factorization, see [4,6].…”