@ARTICLE {
	AUTHOR = "Francisco Claude and Gonzalo Navarro and Alberto Ord{\'o}{\~n}ez",
	TITLE ="The Wavelet Matrix: An Efficient Wavelet Tree for Large Alphabets",
	JOURNAL = "Information Systems",
	VOLUME = "47",
	PAGES = "15-32",
	YEAR = "2015",
	PUBLISHER = "Elsevier Science",
	ADDRESS = "Amsterdam, The Netherlands",
	ISSN = "0306-4379"
	}