1. The Canadian Task Force on the Periodic Health Examination: The Canadian Guide to Clinical Preventive Health Care;Woolf,1994
2. Ethinyl estradiol and dl-norgestrel as a postcoital contraceptive;Yuzpe;Fertil Steril,1977
3. Oral contraception and congenital malformations in offspring: a review and meta-analysis of the prospective studies;Bracken;Obstet Gynecol,1990
4. Randomized controlled trial of levonorgestrel versus the Yuzpe regimen of combined oral contraceptives for emergency contraception;Lancet,1998
5. Mifepristone (RU 486) compared with high dose estrogen and progestogen for emergency postcoital contraception;Glasier;N Engl J Med,1992