Galván-Escobedo, I.G., Ramírez-Arriaga, E., Martínez-Hernández, E., Reyes-Salas, M., Angeles-García, S. and Kohashi-Shibata, J. 2015. Morphological Descriptions Of Late Oligocene – Early Miocene Spores: San Gregorio Formation, Baja California Sur, Mexico. Acta Microscopica. 24, 1 (May 2015), 41-52.