@inproceedings{nikita2011isotropy,
title={Isotropy of unitary involutions},
author={Nikita Karpenko, and Maksim Zhykhovich},
url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170108203401734265779},
booktitle={Acta Mathematica},
volume={211},
number={2},
pages={227-253},
year={2011},
}