Using Trialogues to Measure English Language Skills. - Youngsoon So; Diego Zapata-Rivera; Yeonsuk Cho; Christine Luce; Laura Battistini (J. Educ. Technol. Soc., 2015)

Spoken Text Difficulty Estimation Using Linguistic Features. - Su-Youn Yoon; Yeonsuk Cho; Diane Napolitano (BEA@NAACL-HLT, 2016)