## Bibliography of articles on subnormal matrices

listed in chronological order

- P. R. Halmos, Subnormal operators and the subdiscrete topology,
*Internat.
Ser. Numer. Math. *65, Birkhaüser, Basel, (1984), pp. 4965.
- S. H. Friedberg and A. J. Insel, Hyponormal 2 x 2 matrices are subnormal,
*Linear Algebra Appl. * 175:3138 (1992).
- S. H. Friedberg and A. J. Insel, Characterizations of subnormal matrices,
*Linear Algebra Appl. * 231:113 (1995).
- A. J. Insel, Levels of Subnormality,
*Linear Algebra Appl. * 267:2753
(1997).
- H. J. Woerdeman, Hermitian and Normal Completions, (Unpublished).

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