Janson, H.; Matheisen, K. S. (2008). "Temperament profiles from infancy to middle childhood: Development and associations with behavior problems". Developmental Psychology. 44 (5): 1314–1328. doi:10.1037/a0012713. PMID 18793065.
Coplan, R. J.; Rose-Krasnor, L.; Weeks, M.; Kingsbury, A.; Kingsbury, M.; Bullock, A. (2012). "Alone is a crowd: Social motivations, social withdrawal, and socioemotional functioning in later childhood". Developmental Psychology. 49 (5): 861–875. doi:10.1037/a0028861. PMID 22686178.
