Irwin, O. C. (1941). Research on speech sounds for the first six months of life. Psychological Bulletin, 38, 277-285. [FULLTEXT]
A History of Psycholinguistics
Bibliography for Levelt (2013)

Irwin, O. C. (1941). Research on speech sounds for the first six months of life. Psychological Bulletin, 38, 277-285. [FULLTEXT]