On the Construction of Some Integral Operators for Generalized Axially Symmetric Harmonics and Stream Functions K. Ranger Indiana University Mathematics Journal 1965 text pdf 10.1512/iumj.1965.14.14028 10.1512/iumj.1965.14.14028 en Indiana Univ. Math. J. 14 (1965) 383 - 401 state-of-the-art mathematics http://iumj.org/access/