Daniušis, Povilas, Pranas Vaitkus, and Linas Petkevičius. “Hilbert–Schmidt Component Analysis”. Lietuvos matematikos rinkinys 57, no. A (December 15, 2016): 7–11. Accessed October 27, 2025. https://test.zurnalai.vu.lt/LMR/article/view/14932.