HEFNAWY A.I.; ELSID E.A.; EUAT TALLAH S. Cordial labeling for the sum and union of the second power of paths and stars. Utilitas Mathematica , [S. l.], v. 108, 2018. Disponível em: https://utilitasmathematica.com/index.php/Index/article/view/1294. Acesso em: 7 may. 2026.