1. Anderson, R.N., 1999. United States Lifetables, 1997. National Vital Statistics Reports, December 13, 1999. http://www.cdc.gov/nchs.
2. Fetal and Infant Origins of Adult Disease;Barker,1992
3. Mothers, Babies, and Disease in Later Life;Barker,1994
4. Berkeley Mortality Database. http://demog.berkeley.edu.
5. Mortality among twins age 6;Christensen;British Medical Journal,1995