Cervantes, M., E. Kurm, and shev. “Diffraction of Interfering Waves: Two Optical Beams in the Fresnel Region”. Revista Mexicana De Física, vol. 44, no. 2, Jan. 1998, pp. 136-4, https://rmf.smf.mx/ojs/index.php/rmf/article/view/2748.