Composition Operators on H^p with Dense Range Raymond Roan Indiana University Mathematics Journal 1978 text pdf 10.1512/iumj.1978.27.27013 10.1512/iumj.1978.27.27013 en Indiana Univ. Math. J. 27 (1978) 159 - 162 state-of-the-art mathematics http://iumj.org/access/