Bibliography
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- Collins—The Faculty of Speech
- Huey—Psychology and Pedagogy of Reading
- Woolbert—The Fundamentals of Speech
- Blanton—Speech Training for Children
- Starr—Some Steps in Human Progress
- Wyllie—Disorders of Speech
- Störring—Mental Pathology in its Relation to Normal Psychology
- Huston—The Story of Language
- Stewart—Moral Sentiments
- Burnett—The Origin and Progress of Language
- MacNamara—Human Speech
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- Noire—The Origin and Philosophy of Language
- LeFevre—Race and Language