HMISSI, Farida. On energy formulas for symmetric semigroups. Annales Mathematicae Silesianae, [S. l.], v. 19, p. 7–18, 2005. Disponível em: https://journals.us.edu.pl/index.php/AMSIL/article/view/14079. Acesso em: 5 dec. 2025.