Magic square. Baghdad Science Journal, Iraq, Baghdad, v. 6, n. 3, p. 618–620, 2009. DOI: 10.21123/bsj.2009.6.3.618-620. Disponível em: https://bsj.uobaghdad.edu.iq/index.php/BSJ/article/view/1024.. Acesso em: 18 may. 2024.