Bibliography of articles on subnormal matrices
listed in chronological order

1. P. R. Halmos, Subnormal operators and the subdiscrete topology, Internat. Ser. Numer. Math. 65, Birkhaüser, Basel, (1984), pp. 49­65.
2. S. H. Friedberg and A. J. Insel, Hyponormal 2 x 2 matrices are subnormal, Linear Algebra Appl.   175:31­38 (1992).
3. S. H. Friedberg and A. J. Insel, Characterizations of subnormal matrices, Linear Algebra Appl.   231:1­13 (1995).
4. A. J. Insel, Levels of Subnormality, Linear Algebra Appl.   267:27­53 (1997).
5. H. J. Woerdeman, Hermitian and Normal Completions, (Unpublished).

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