@inbook {,
	title = {Mass-Distance Meaures for the Maya Obsidian Trade},
	booktitle = {Exchange systems in prehistory},
	series = {Studies in archeology},
	year = {1977},
	note = {76013933 //r91edited by Timothy K. Earle, Jonathon E. Ericson.Includes bibliographies and index.},
	pages = {91-107},
	publisher = {Academic Press},
	organization = {Academic Press},
	address = {New York},
	keywords = {Commerce, Prehistoric},
	isbn = {0122276507},
	author = {Sidrys, Raymond V.},
	editor = {Earle, Timothy K. and Ericson, Jonathon E.}
}