BAXTER, I. F. G. Line Elements in Physics. The Journal of the Indian Mathematical Society, [S. l.], v. 26, n. 1-2, p. 25–33, 1962. DOI: 10.18311/jims/1962/16876. Disponível em: https://informaticsjournals.com/index.php/jims/article/view/16876. Acesso em: 27 apr. 2024.