JÓNSSON, T. Comparision of the length of infinite geodesics in manifolds with nonpositive curvature. MATHEMATICA SCANDINAVICA, [S. l.], v. 51, p. 151–157, 1982. DOI: 10.7146/math.scand.a-11969. Disponível em: https://www.mscand.dk/article/view/11969. Acesso em: 3 may. 2024.