An Indicator Diagram Theory for Finitely Normal Families of Analytic Functions Alan Wilson Indiana University Mathematics Journal 1961 text pdf 10.1512/iumj.1961.10.10036 10.1512/iumj.1961.10.10036 en Indiana Univ. Math. J. 10 (1961) 547 - 555 state-of-the-art mathematics http://iumj.org/access/