de Azcarate, JG; Cleef, AM; Trapaga, AG; Almeida, L
(2004)
This study of the zacatonal alpino zone of the volcanoes Popocatepetl (5452 in) and Nevado de Toluca (4690 m) in the central region of the Transmexican Volcanic Belt, is a follow-up of the study of ALMEIDA et al. (1994). ...