The Discs Structures of A4-Graph for the Held Group. Iraqi Journal of Science, [S. l.], v. 63, n. 8, p. 3612–3617, 2022. DOI: 10.24996/ijs.2022.63.8.35. Disponível em: https://ijs.uobaghdad.edu.iq/index.php/eijs/article/view/7490.. Acesso em: 6 may. 2024.