RT Journal Article SR Electronic T1 ORAL CONTRACEPTIVES AND VENOUS THROMBOSIS JF The Journal of the Royal College of General Practitioners JO J R Coll Gen Pract FD British Journal of General Practice SP 904 OP 905 VO 25 IS 161 A1 Kay, Clifford R. YR 1975 UL http://bjgp.org/content/25/161/904.abstract AB