ZINOVIEV, A. Termal Equations and Finite Controllability. Ann. Sofia Univ. Fac. Math. and Inf., [S. l.], v. 93, p. 49–54, 2001. Disponível em: https://stipendii.uni-sofia.bg/index.php/fmi/article/view/202. Acesso em: 4 dec. 2024.