TOMNO, Victor; NYAMWALA, Fredrick; KAMAKU, Waweru. The Wss P0 Matrix Completion Problem for Symmetric Patterns of Acyclic Digraphs of Order Four. International Journal of Sciences: Basic and Applied Research (IJSBAR), Jordan, v. 37, n. 1, p. 112–121, 2018. Disponível em: https://www.gssrr.org/JournalOfBasicAndApplied/article/view/8591. Acesso em: 4 jun. 2026.