RT Journal Article SR Electronic T1 MSSVD JF Genitourinary Medicine JO Genitourin Med FD BMJ Publishing Group Ltd SP 138 OP 138 DO 10.1136/sti.61.2.138 VO 61 IS 2 A1 M A Waugh YR 1985 UL http://sti.bmj.com/content/61/2/138.abstract AB