HENNING, MICHAEL A.; OELLERMANN, ORTRUD R. Bipartite Ramsey theorems for multiple copies of K2,2. Utilitas Mathematica , [S. l.], v. 54, 1998. Disponível em: https://utilitasmathematica.com/index.php/Index/article/view/95. Acesso em: 8 may. 2026.