1. Alberman E, Creasy M, Elliott M, Spicer C (1976) Maternal factors associated with fetal chromosomal anomalies in spontaneous abortions. Br J Obstet Gynaecol 83: 621–627
2. Bernheim A, Chastang C, de Heaulme M, de Grouchy J (1979) Excès de garçons dans la trisomie 21. Ann Genet (Paris) 22: 112–114
3. Boué A, Thibault C (eds) (1973) Les accidents chromosomiques de la reproduction. Centre International de l’Enfance, Paris
4. Boylan P, O’Brien N (1977) Down’s syndrome. J Irish Med Assoc 70: 122–123
5. Carr DH (1970) Chromosome studies in selected spontaneous abortions: 1. Conception after oral contraceptives. Can Med Assoc J 103: 343–348