@inproceedings{enrique1992on,
title={On a theorem of Baernstein},
author={Enrique Villamor},
url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170108203545620381642},
booktitle={Arkiv for Matematik},
volume={33},
number={1},
pages={183-197},
year={1992},
}