Mathematical Inequalities & Applications · Volume 21, Issue 3 Infinite series formula for Hübner upper bound function with applications to Hersch-Pfluger distortion function 21-46 Pages 629-648 DOI 10.7153/mia-2018-21-46 Downloads Short PDF Full PDF PNG Authors Miao-Kun Wang Song-liang Qiu Yuming Chu Keywords infinite series formula Hübner upper bound function Hersch-Pfluger distortion function quasiconformal mappings Ramanujan modular equation Subject classes 33C62 33E05