VILKAS, E. On solving of the functional equation with a game value operator. Lithuanian Mathematical Journal, [S. l.], v. 3, n. 1, p. 61–70, 1963. DOI: 10.15388/LMJ.1963.19406. Disponível em: https://journals.vu.lt./LMJ/article/view/19406. Acesso em: 27 apr. 2025.