Comments on Normal Toeplitz Matrices by Farenick

It would be correct to add that the main contribution of [2] was to prove, for arbitrary n, the necessity of some equalities for the entries of a normal Toeplitz matrix of order n. These equalities are in fact equivalent to the authors’ equations (1) in the real case. The full solution of the problem (of describing normal Toeplitz matrices) for the real case was given in [3]. The same year another and very elegant solution of the real problem was published in [4]. The paper [5] in the February 1996 issue of Computational Mathematics and Mathematical Physics solves the complex version of the problem, i.e., the version the authors of [1] are dealing with. A different and, again, quite ingenious proof is to appear this year in the November issue of the journal mentioned above [6].