 Social and emotional messages of smiling by Robert E. Kraut and others

Primary publication: doi.org/10.1037/0022-3514.37.9.1539

Publication text or primary record: kraut.hciresearch.info/wp-content/uploads/kraut79-SocialEmotionalMessagesOfSmiling-1.pdf

Journal of Personality and Social Psychology 37, 1539–1553; naturalistic observations of bowling and social engagement.