@book{44820,
	author = {Heiken, Grant.},
	title = {An atlas of volcanic ash.},
	publisher = {Smithsonian Institution Press; [for sale by the Supt. of Docs., U.S. Govt. Print. Off.]},
	year = {1974.},
	series = {Smithsonian contributions to the earth sciences},
	address = {Washington},
	note = {921004}
}