OBERLACK, M.; WACŁAWCZYK, M. On the extension of Lie group analysis to functional differential equations. Archives of Mechanics, Warsaw, Poland, v. 58, n. 6, p. 597–618, 2006. Disponível em: https://am.ippt.pan.pl/index.php/am/article/view/v58p597. Acesso em: 10 jan. 2026.