1. Scottish Health Service Common Services Agency. Scotland birthweight, head circumference and length for gestational age;Information; Division, Statistics,1992
2. Weight at birth among Genet,1980
3. Twins: measures of birth size at different gestational ages;Wilson, R.S.,1974
4. Growth differences in twin pregnancy;Daw, E.; Walker, J.;BrJ ClinPract,1975
5. Human multiple reproduction;In, MacGillivray I.,1975