Galindo, Ignacio, and J. L. Bravo. “On the Presence of a Volcanic Stratospheric Dust Stratum over a Polluted Atmosphere: Mexico City”. Geofisica Internacional 15, no. 2 (April 1, 1975): 157–167. Accessed July 3, 2024. http://revistagi.geofisica.unam.mx/index.php/RGI/article/view/1512.