@book{543881,
	author = {Durell, Clement V. and Robson, A.},
	title = {Advanced trigonometry /},
	publisher = {G. bell and son ltd:},
	year = {c1953},
	address = {London:},
	edition = {Dover Ed.},
	note = {Includes index.},
	url = {http://www.loc.gov/catdir/enhancements/fy0614/2003057276-d.html}
}