Guillot Ortiz, Daniel and Piet Van der Meer. “Agave americana var. oaxacensis y el icono de Valentini (1719)”. Botanica Complutensis, vol. 28, vol. 28, 2005, pp. 101-3, https://revistas.ucm.es/index.php/BOCM/article/view/BOCM0404110101A.