Rabanovich, V. I. “Decomposition of a Hermitian Matrix into a Sum of a Fixed Number of Orthoprojections”. Ukrains’kyi Matematychnyi Zhurnal 72, no. 5 (April 29, 2020): 679–693. Accessed October 7, 2022. http://umj.imath.kiev.ua/index.php/umj/article/view/2378.