D, J., F. Granados-Agustín, and A. Cornejo-Rodríguez. “Measurements of Local Radii of Curvature by the Retrocollimated Interferometric Method”. Revista Mexicana De Física, vol. 54, no. 3, Jan. 2008, pp. 194-0, https://rmf.smf.mx/ojs/index.php/rmf/article/view/3608.