@inproceedings{xin2014extensions,
  title={Extensions of Wielandt’s Min-max Principles for Positive Semi-Definite Pencils},
  author={Xin Liang, and Ren-Cang Li},
  url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20220424220000465284116},
  booktitle={Linear Multilinear Algebra},
  volume={62},
  number={8},
  pages={1032-1048},
  year={2014},
}
             
            
                
Xin Liang, and Ren-Cang Li. Extensions of Wielandt’s Min-max Principles for Positive Semi-Definite Pencils. 2014. Vol. 62. In Linear Multilinear Algebra. pp.1032-1048. http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20220424220000465284116.