On Quasiconformal Mappings James Jenkins Indiana University Mathematics Journal 1956 text pdf 10.1512/iumj.1956.5.55013 10.1512/iumj.1956.5.55013 en Indiana Univ. Math. J. 5 (1956) 343 - 352 state-of-the-art mathematics http://iumj.org/access/