PROKIP, V. M. On the solvability of the Riccati matrix algebraic equation. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 46, n. 11, p. 1591–1593, 1994. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/5602. Acesso em: 5 dec. 2025.