“…In other schemes advantage is taken of the special forms of some implicit methods [2], [4], [5], [12]. In another approach, schemes based directly on iterative procedure have been developed [3], [8], [9], [10], [13], [21]. For a singly implicit method, there is a non-singular matrix S so that S −1 AS = λ(I s − L) −1 , where L is zero except for some ones on the sub-diagonal.…”