1. The Theory of Subnormal Operators;Conway,1991
2. Lectures on Hyponormal Operators;Martin,1989
3. Linear operators for which T∗T and T∗+T commute;Campbell;Pacific J. Math.,1975
4. Linear operators for which T∗T and T∗+T commute III;Campbell;Pacific J. Math.,1978
5. Spectral properties of linear operators for which T∗T and T∗+T commute;Campbell;Proc. Amer. Math. Soc.,1976