RT Journal Article SR Electronic T1 THE PLACENTA IN TWIN PREGNANCY JF Journal of Clinical Pathology JO J Clin Pathol FD BMJ Publishing Group Ltd and Association of Clinical Pathologists SP 678 OP 678 DO 10.1136/jcp.21.5.678-b VO 21 IS 5 A1 Claud W. Taylor YR 1968 UL http://jcp.bmj.com/content/21/5/678.2.abstract AB