Cita APA

Otta, E., & Sarra, S. (1990). A study about the smile and the laughing in children of four and five years old.

Citación estilo Chicago

Otta, Emma, y Simone Sarra. A Study About the Smile and the Laughing in Children of Four and Five Years Old. 1990.

Cita MLA

Otta, Emma, y Simone Sarra. A Study About the Smile and the Laughing in Children of Four and Five Years Old. 1990.