by 엄희정(Hee Jung Eum), 김희철(Hee-Cheol Kim), 노경원(Kyeong-Won Roh)
Published in 한국정보통신학회논문지 (2019)

by 조용경(Yong-Kyung Cho), 권도하(Do-Ha Kwon)
Published in 언어치료연구 (2004)