THAULE, M. On Open and Closed Strings. MATHEMATICA SCANDINAVICA, [S. l.], v. 119, n. 2, p. 223–236, 2016. DOI: 10.7146/math.scand.a-24744. Disponível em: https://www.mscand.dk/article/view/24744. Acesso em: 7 apr. 2025.