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How Twins Work

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These are some sources that we found useful in researching this article:


  • Stedman's Medical Dictionary, 27th edition
  • The Concise Science Encyclopedia, Kingfisher Publications
  • Entwined Lives: Twins and what they tell us about human behavior by Nancy L. Segal, Ph.D.
  • Twins and What They Tell Us About Who We Are by Lawrence Wright
  • Twins: An Uncanny Relationship by Peter Watson
  • Twins! Pregnancy, Birth and the First Year of Life by Connie Agnew, M.D., Alan Klein, M.D. and Jill Alison Ganon
  • The Art of Parenting Twins by Patricia Maxwell Malmstrom and Janet Poland

Articles, Journals and Periodicals

  • National Vital Statistics Reports
  • "Fetus In Fetu: A Case Report" by SV Phatak, PK Kolwadkar, MS Phatak: Ind J Radiol Imag 2003 13:1:93-94
  • "Larger Women More Likely to Have Twins" by Emma Baines, GP: Obstet Gynecol 2005
  • "Twin Language: A Risk Factor for Language Impairment?" by D.V.M. Bishop, S.J. Bishop: Journal of Speech, Language & Hearing Research, February 1998, Vol. 41, Issue 1

Web References

  • CBS News, 48 Hours
  • Internet Movie Database
  • The Twin to Twin Transfusion Syndrome Foundation
  • The Minnesota Twin Family Study