Jade in Ancient Costa Rica (New York: Metropolitan Museum of Art, c1998), ed. by Julie Jones, contrib. by Mark Miller Graham, Juan Vincente Guerrero M., Michael J. Snarskis, and Zulay Soto Mendez (page images and PDF at Metropolitan Museum of Art and Google)
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http://www.metmuseum.org/research/metpublications/Jade_in_Ancient_Costa_Rica
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