%0 Journal Article %A Schôichi Ôta %T $q$-deformed circularity for an unbounded operator in Hilbert space %J Colloquium Mathematicum %D 2010 %P 191-199 %V 120 %N 2 %I mathdoc %U http://geodesic.mathdoc.fr/articles/10.4064/cm120-2-2/ %R 10.4064/cm120-2-2 %G en %F 10_4064_cm120_2_2