The dysphonia severity index: an objective measure of vocal quality based on a multiparameter approach. - Wuyts,F.L.; De Bodt,M.S.; Molenberghs,G.; Remacle,M.; Heylen,L.; Millet,B.; Van Lierde,K.; Raes,J.; Van de Heyning,P.H. (Journal of Speech, Language, & Hearing Research, 2000)