1. Operators commuting with a weighted shift;Gellar, Ralph;Proc. Amer. Math. Soc.,1969
2. R. L. Kelley, Weighted shifts on Hilbert space, Thesis, Univ. of Michigan, 1966, pp. 19-33.
3. W. C. Ridge, Composition operators, Thesis, Indiana Univ., 1969, pp. 47-69.