M. Kilgo

Evaluation of a stuttering treatment based on reduction of short phonation intervals.

R. Ingham, J. Ingham, R J Ingham, 2001, Journal of speech, language, and hearing research : JSLHR.

Efficacy of the Modifying Phonation Intervals (MPI) Stuttering Treatment Program With Adults Who Stutter.

Anne K. Bothe, R. Ingham, Yuedong Wang, 2015, American journal of speech-language pathology.