@inproceedings{m.1985regularity,
title={Regularity for stationary surfaces of constant mean curvature with free boundaries},
author={M. Grüter, S. Hildebrandt, and J. C. C. Nitsche},
url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170108203306093956383},
booktitle={Acta Mathematica},
volume={156},
number={1},
pages={119-152},
year={1985},
}
M. Grüter, S. Hildebrandt, and J. C. C. Nitsche. Regularity for stationary surfaces of constant mean curvature with free boundaries. 1985. Vol. 156. In Acta Mathematica. pp.119-152. http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170108203306093956383.