Author,Title,Edition,Publisher,Year,Series,Number,ISBN,ISSN,URL
"Vaccai, Nicola and Paton, John Glenn",Practical method of Italian singing,"New ed., for mezzo-soprano (alto) or baritone",Schirmer,1975,Schirmer's library of musical classics,,079355120X,,https://cir.nii.ac.jp/crid/1130000795425851008