@book{26556,
	author = {Behre, Chas. H.},
	title = {Slate in Northampton County, Pennsylvania,},
	publisher = {Dept. of Forests and Waters, Topographic and Geologic Survey,},
	year = {1927.},
	series = {Pennsylvania. Topographic and Geologic Survey. Bulletin M9},
	address = {Harrisburg, Pa.,},
	note = {At head of title: Pennsylvania Geological Survey, fourth series.}
}