Social smiling in normal and down syndrome infants: A comparative study

Ethology and Sociobiology - Tập 10 - Trang 413 - 1989
Fernando Carvajal1, Angela Loeches1, Jaime Iglesias1
1Dpto. de Psicologia Biológica y de la Salud Facultad de Psicologia. Universidad Autónoma de Madrid Canto Blanco, 28049 Madrid, Spain