Weikang Yu, Hu Yang, Shengguo Li, and Yanlin Xu. “An HSS-Matrix-Based Fast Direct Solver With Randomized Algorithm”. The Applied Computational Electromagnetics Society Journal (ACES) 33, no. 07 (July 22, 2021): 814–817. Accessed July 5, 2022. https://journals.riverpublishers.com/index.php/ACES/article/view/9091.