1. G. A. Miller,Language and Communication (McGraw-Hill Book Co., Inc., New York 1951).
2. R. Potter, G. A. Kopp undH. C. Green,Visible Speech (Van Nostrand, New York 1947).
3. S. Karelitz, R. Karelitz undL. Rosenfeld,Cry Study (Long Island Jewish Hospital, New Hyde Park, N. Y. 1959).
4. J. Lind, persönliche Mitteilung (1962).