PMID 17168158. Hallmayer, Joachim. Genetic Heritability and Shared Environmental Factors Among Twin Pairs With Autism. Archives of General Psychiatry. 1 November
Luce, Carol; Kraus, Stephen J. The Heritabilityof Characteristics Associated with Dispositional Empathy. Journal of Personality. 1994-09, 62 (3): 369–391