Comments on "Stabilisability and detectability of discrete-time time-varying systems" by J.C. Engwerder

An alleged counterexample in the above-titled paper (ibid., vol.35, no.4, pp.425-429, Apr. 1990) to a main result of B.D.O. Anderson and J.B. Moore (SIAM J. Contr. Optimiz., vol.19, no.1, pp.22-32, 1981) is shown not to be a counterexample in actuality.<
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