@book{1994,
	author = {Liljedahl, John B.},
	title = {Tractions and their power units /},
	publisher = {CBS Publishers & Distributors,},
	year = {2004.},
	address = {[S.l.] :},
	url = {http://www.amazon.com/exec/obidos/ASIN/8123905017/chopaconline-20}
}