@book{56693,
	author = {Cohen, Morris Raphael, and Nagel, Ernest,},
	title = {An introduction to logic and scientific method /},
	publisher = {George Routledge & Sons,},
	year = {1934 [reprint 1972] },
	address = {London :},
	note = {Also published: New York : Harcourt, Brace, 1934.}
}