@inproceedings{dmitry1999best,
title={Best approximation in the supremum norm by analytic and harmonic functions},
author={Dmitry Khavinson, and Harold S. Shapiro},
url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170108203602688269775},
booktitle={Arkiv for Matematik},
volume={39},
number={2},
pages={339-359},
year={1999},
}
Dmitry Khavinson, and Harold S. Shapiro. Best approximation in the supremum norm by analytic and harmonic functions. 1999. Vol. 39. In Arkiv for Matematik. pp.339-359. http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170108203602688269775.