References
- Fletcher, C. 1970 Escapable errors in employing ethnohistory to archaeology. American Antiquity, 35:209–213.
- Graham, J. and R. Heizer 1968 Notes on the Papalhuapa site, Guatemala. Contributions of the University of California Archaeological Research Facility, 5:101–125.
- Hester, Thomas R. 1972 Notes on large obsidian blade cores and core-blade technology in Mesoamerica. Contributions of the University of California Archaeological Research Facility, 14:95–106.
- 1975 The obsidian industry of Beleh (Chinautla Viejo), Guatemala. International Congress of Americanists, 1974, Mexico: 1:473.
- Sheets, Payson 1972 A model of Mesoamerican obsidian technology based on Preclassic workshop debris in El Salvador. Ceramica de Cultura Maya, 8:17–33.
- 1975a A reassessment of the Precolumbian obsidian industry of El Chayal, Guatemala. American Antiquity, 40:98–103.
- 1975b Behavioral analysis and the structure of a prehistoric industry. Current Anthropology, 16:3.
- Sidrys, Raymond, John Andresen and Derek Marcucci 1976 Obsidian sources in the Maya area. Journal of New World Archaeology, 1:5.