1. Fifty psychological and psychiatric terms to avoid: a list of inaccurate, misleading, misused, ambiguous, and logically confused words and phrases;Lilienfeld;Front. Psychol.,2015
2. Merriam-Webster Dictionary, Fraternal, 2015. Available from: http://www.merriam-webster.com/dictionary/fraternal
3. The Genain Quadruplets;Rosenthal,1963
4. Born Together-Reared Apart: The Landmark Minnesota Twin Study;Segal,2012
5. N. Segal (2012). The mean ages of the twins in four of the studies ranged from 26.1 to 51.4 years, while the twins in the fifth study were drawn from a sample of twins with a mean age of 65.6 years, Cambridge, MA.