@booklet {5758,
	title = {CLAPP, C.H. 1921. Geology of the igneous rocks of Essex County, Massachusetts. Bulletin, United States Geological Survey, 704: 1-132.},
	year = {1921},
	note = {CLAPP, C.H. 1921. Geology of the igneous rocks of Essex County, Massachusetts. Bulletin, United States Geological Survey, 704: 1-132.}
}
