BURGER A.P.; Grun̈dlingh W.R.; VAN VUUREN J.H. Two combinatorial problems involving lottery schemes: Characterising solution set structures. Utilitas Mathematica , [S. l.], v. 75, 2008. Disponível em: https://utilitasmathematica.com/index.php/Index/article/view/577. Acesso em: 8 may. 2026.