(en-US) Mervyn Rothstein, «'PHANTOM OF THE OPERA' WINS SEVEN TONYS; BEST PLAY: 'BUTTERFLY' (Published 1988)», The New York Times, (ISSN0362-4331, lire en ligne, consulté le )
(en-US) Mervyn Rothstein, «'PHANTOM OF THE OPERA' WINS SEVEN TONYS; BEST PLAY: 'BUTTERFLY' (Published 1988)», The New York Times, (ISSN0362-4331, lire en ligne, consulté le )