@book{17278,
	author = {Putnam, William Clement, and Webb, Robert Wallace,},
	title = {Laboratory exercises in physical geology,},
	year = {1934.},
	address = {Los Angeles, Calif.,},
	note = {"... The section on rocks and minerals was written by Webb, the part dealing with physiography and the use of topographic maps is by Putnam."--Pref.}
}