Skelly, Robert, Anne Ford, Glenn Summerhayes, Jerome Mialanes, and Bruno David. 2016. “Chemical Signatures & Social Interactions: Implications of West Fergusson Island Obsidian at Hopo, East of the Vailala River (Gulf of Papua), Papua New Guinea”. Journal of Pacific Archaeology 7 (1):126-38. https://doi.org/10.70460/jpa.v7i1.186.