OSTROVSKYI, V. L. Centered one-parameter semigroups. Methods of Functional Analysis and Topology, [S. l.], v. 10, n. 2, p. 32–42, 2004. Disponível em: https://zen.imath.kiev.ua/index.php/mfat/article/view/239. Acesso em: 17 dec. 2025.