1. Obsidian in the south-central Andes: geological, geochemical, and archaeological assessment of north Patagonian sources (Argentina);Barberena;Quaternary International,2011
2. PXRF/WDXRF inter-unit data comparison of Arizona obsidian samples;Dybowski;Journal of Arizona Archaeology,2012
3. Frahm, E., 2007. An evaluation of portable X-ray fluorescence for artifact sourcing in the field: can handheld devices differentiate Anatolian obsidian sources? Paper Presented at the 2007 Annual Meeting of the Geological Society of America. Presentation. Available on-line: https://gsa.confex.com/gsa/viewHandout.cgi?uploadid=250.
4. Frahm, E., 2010. The Bronze-age Obsidian Industry at Tell Mozan (Ancient Urkesh), Syria. Ph.D. dissertation, Department of Anthropology, University of Minnesota. Available online at University of Minnesota's Digital Conservancy: http://purl.umn.edu/99753.
5. Evaluation of archaeological sourcing techniques: reconsidering and re-deriving Hughes' four-fold assessment scheme;Frahm;Geoarchaeology,2012