@inproceedings{albert1973integral,
title={Integral means, univalent functions and circular symmetrization},
author={Albert Baernstein II},
url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170108203233342036177},
booktitle={Acta Mathematica},
volume={133},
number={1},
pages={139-169},
year={1973},
}
Albert Baernstein II. Integral means, univalent functions and circular symmetrization. 1973. Vol. 133. In Acta Mathematica. pp.139-169. http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170108203233342036177.