MERKYS, V. Über das Integrieren eines linearen Systems von Differentialgleichun gen in geschlossener Form. Lithuanian Mathematical Journal, [S. l.], v. 8, n. 2, p. 289–295, 1968. DOI: 10.15388/LMJ.1968.20216. Disponível em: https://www.journals.vu.lt/LMJ/article/view/20216.. Acesso em: 7 may. 2024.