VOLKMANN, L. Weak Signed Roman Domination in Digraphs. Tamkang Journal of Mathematics, [S. l.], v. 52, n. 4, p. 497–508, 2021. DOI: 10.5556/j.tkjm.52.2021.3523. Disponível em: https://journals.math.tku.edu.tw/index.php/TKJM/article/view/3523. Acesso em: 22 jul. 2024.