Walter O Spitzer, Michael A Lewis, Lothar A J Heinemann, Margaret Thorogood
Spitzer W O, Lewis M A, Heinemann L A J, Thorogood M.
Third generation oral contraceptives and risk of venous thromboembolic disorders: an international case-control study
BMJ 1996; 312 :83
doi:10.1136/bmj.312.7023.83