Fuchsian Groups of Convergence Type and Poincare Series of Dimension - 2 K. Rajeswara Rao Indiana University Mathematics Journal 1969 text pdf 10.1512/iumj.1969.18.18050 10.1512/iumj.1969.18.18050 en Indiana Univ. Math. J. 18 (1969) 629 - 644 state-of-the-art mathematics http://iumj.org/access/