1. Frequency of twin births in developed countries;Pison;Twin Res Hum Genet,2006
2. Multiple pregnancy: the management of twin and triplet pregnancies in the antenatal period,2011
3. Why mothers die 2000–2002. Report on confidential enquiries into maternal deaths in the United Kingdom,2004
4. How does multiple pregnancy affect maternal mortality and morbidity?;Senat;Clin Obstet Gynecol,1998
5. Adverse outcome after multiple pregnancy;Petterson;Baillieres Clin Obstet Gynaecol,1998