@ARTICLE {Bruno96,
	AUTHOR = "William J. Bruno",
	YEAR = "1996" ,
	JOURNAL = "Mol. Biol. Evol." ,
	VOLUME = "13" ,
	NUMBER = "10" ,
	MONTH = "December" ,
	PAGES = "1368--1375" ,
	TITLE = " Modeling Residue Usage in Aligned Protein Sequences
		  via Maximum Likelihood" 
	}