TRUSCHINA, L. Über zweifache inhomogene Systeme von Differenzengleichungen. Lithuanian Mathematical Journal, [S. l.], v. 11, n. 2, p. 383–395, 1971. DOI: 10.15388/LMJ.1971.20999. Disponível em: https://journals.vu.lt./LMJ/article/view/20999. Acesso em: 27 apr. 2025.