Includes a list of Malde files in the U.S. Geological Survey, Field Records Library, Denver, Colorado, concerning the geology and stratigraphy of the Valsequillo area, Puebla, Mexico with special reference to the Hueyatlaco archaeologic site. Other Valsequillo/Hueyatlaco materials are included in the Malde papers archived at the Denver Museum of Nature and Science.
Geology and Stratigraphy of the Valsequillo Area, Puebla, Mexico. (1964-1966, 1968, 1970, 1973)
Hal Malde's letter to Guillermo Salas concerning Jose Luis Lorenzo (1967)