@book{53443,
	author = {Gardener, Mark. and ebrary, Inc.},
	title = {The essential R reference},
	publisher = {J. Wiley & Sons, Inc.,},
	year = {2013.},
	address = {Indianapolis, Ind. :},
	note = {Includes index.},
	url = {http://site.ebrary.com/lib/rucke/Doc?id=10629602}
}