Clustering and socially-directed behaviors in a playgroup of 1-yr-old boys.
D002652:Child Behavior; D002657:Child Development; D003142:Communication; D005133:Eye Movements; D006801:Humans; D007223:Infant; D008297:Male; D009769:Object Attachment; D010379:Peer Group; D010988:Play and Playthings; D012904:Smiling; D012919:Social Behavior; D013997:Time Factors