RT Journal Article SR Electronic T1 Embryology of the heart JF Heart JO Heart FD BMJ Publishing Group Ltd and British Cardiovascular Society SP 5 OP 5 DO 10.1136/hrt.81.1.5 VO 81 IS 1 A1 M K DAVIES A1 A HOLLMAN YR 1999 UL http://heart.bmj.com/content/81/1/5.abstract AB