Levstein, Fernando, and Carolina Maldonado. “Generalized Quadrangles and Subconstituent Algebra”. CUBO, A Mathematical Journal 12, no. 2 (June 1, 2010): 53–75. Accessed April 29, 2024. https://www.perspectivasdelacomunicacion.cl/ojs/index.php/cubo/article/view/1407.