Abstract
Hyponormality, normality and subnormality for unbounded operators on Hilbert space are investigated and quasi- similarity of such operators is discussed.
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Ôta, S., Schmüdgen, K. On some classes of unbounded operators. Integr equ oper theory 12, 211–226 (1989). https://doi.org/10.1007/BF01195114
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DOI: https://doi.org/10.1007/BF01195114