TY  - SER
AU  - Sheets, Payson.
TI  - Obsidian sources and elemental analyses of aritfacts in southern mesoamerica and the Northern Intermediate Area
T2  - American Antiquity ; 
PY  - 1990///
CY  - Washington-US : 
PB  - Society for American Archaeology, 
N1  - Artículo dentro de: Reports
ER  -