Owens, J. R., Harris, F., Walker, S., McAllister, E., & West, L. (1983). The incidence of Down's syndrome over a 19-year period with special reference to maternal age.

Owens, J R., F. Harris, S. Walker, E. McAllister, and L. West. The Incidence of Down's Syndrome Over a 19-year Period With Special Reference to Maternal Age. 1983.

Owens, J R., et al. The Incidence of Down's Syndrome Over a 19-year Period With Special Reference to Maternal Age. 1983.