Boichuk О. A.; KRIVOSHEYA, S. A. Criterion of the solvability of matrix equations of the Lyapunov type. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 50, n. 8, p. 1021–1026, 1998. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/4851. Acesso em: 5 dec. 2025.