Comparison between bone-conducted ultrasound and audible sound in speech recognition. - Yamashita, Akinori; Nishimura, Tadashi; Nagatani, Yoshiki; Okayasu, Tadao; Koizumi, Toshizo; Sakaguchi, Takefumi; Hosoi, Hiroshi (Acta Oto-Laryngologica (Supplement), 2009)