Marín Uribe, Rigoberto, and Isabel Guzmán Ibarra. “One Hundred Years of the Planetary Thinker”. IE Revista de Investigación Educativa de la REDIECH 12 (December 20, 2021): e1515. Accessed August 30, 2025. https://mail.rediech.org/ojs/2017/index.php/ie_rie_rediech/article/view/1515.