توأم: الفرق بين النسختين

* {{Cite book|first=Elyse |last=Schein |author2=Paula Bernstein |title=Identical Strangers: A Memoir of Twins Separated and Reunited |publisher=Random House |location=New York |year=2007 |pages= |isbn=1-4000-6496-1 |oclc=123390922}}

* {{Cite journal|last=Helle |first=Samuli |author2=Virpi Lummaa |author3=Jukka Jokela |year=2004 |title=Selection for Increased Brood Size in Historical Human Populations |journal=Evolution |volume=58 |pages=430–436 |doi=10.1111/j.0014-3820.2004.tb01658.x |url=http://www.huli.group.shef.ac.uk/helleevolution2004.pdf |archive-url=https://web.archive.org/web/20081002173043/http://www.huli.group.shef.ac.uk/helleevolution2004.pdf |dead-url=yes |archive-date=2008-10-02 |format=PDF|accessdate=2008-10-02 |pmid=15068359 |issue=2}}

* {{cite web|url=http://www3.telus.net/tyee/multiples/index.html |archive-url=http://arquivo.pt/wayback/20091015164305/http://www3.telus.net/tyee/multiples/index.html |dead-url=yes |archive-date=2009-10-15 |title=Facts About Multiples: An Encyclopedia of Multiple Birth Records |accessdate=2008-10-18 |first=Jennifer |last=Samson}}

* Am J Med Genet C Semin Med Genet. 2009 May 15;151C(2):136-41. Not really identical: epigenetic differences in monozygotic twins and implications for twin studies in psychiatry. Haque FN, Gottesman II, Wong AH.