NARANIENGAR, M. T. The Spherical Mean Centre. The Journal of the Indian Mathematical Society, [S. l.], v. 6, n. 1, p. 3–11, 1914. DOI: 10.18311/jims/1914/17706. Disponível em: https://www.informaticsjournals.com/index.php/jims/article/view/17706. Acesso em: 6 may. 2024.