RT Journal Article SR Electronic T1 Getting knotted: umbilical knots in a monochorionic monoamniotic twin pregnancy JF Archives of Disease in Childhood - Fetal and Neonatal Edition JO Arch Dis Child Fetal Neonatal Ed FD BMJ Publishing Group Ltd and Royal College of Paediatrics and Child Health SP F24 OP F24 DO 10.1136/adc.2004.061812 VO 90 IS 1 A1 A A A Omari A1 D Cameron YR 2005 UL http://fn.bmj.com/content/90/1/F24.abstract AB