STOROZH, O.G. Maximal nonnegative and $\theta$-accretive extensions of a positive definite linear relation. Carpathian Mathematical Publications, [S. l.], v. 12, n. 2, p. 289–296, 2020. DOI: 10.15330/cmp.12.2.289-296. Disponível em: https://journals.pnu.edu.ua/index.php/cmp/article/view/3921. Acesso em: 18 apr. 2024.