Comments on "On the nature of the Boxer-Thaler and Madwed integrators and their applications in digitizing a continuous-time system" by C.-H. Wang et al

In the above-titled paper by C.-H. Wang et al. (ibid., vol.35, p.1163-7, Oct. 1990) some very interesting and useful techniques were presented for implementing several operational substitution methods for discretizing a continuous-time system. An attempt was made to prove that the Boxer-Thaler method is more accurate than the Madwed method since ´no proof has been seen regarding this fact.´ This fact is indeed shown to be true later in the paper. The purpose of this comment is to refer any interested parties to an earlier proof of this fact.<>