1. Fujisaki. H., & Kawashima, T.On the modes and mechanisms of speech perception. Research on Information Processing, Annual Report No. 2, University of Tokyo, Division of Electrical Engineering, Engineering Research Institute, 1969, 67–73.
2. Miyawaki, K.A preliminary study of American English /r/ by use of dynamic palatography. Annual Bulletin, Research Institute of Logopedics and Phoniatrics, Faculty of Medicine, University of Tokyo, 1972, 6, 19-24.