Lidegaard, Øjvin; Øjvind Lidegaard, Lars Hougaard Nielsen, Charlotte Wessel Skovlund, and Ellen Løkkegaard (2012). "Venous thrombosis in users of non-oral hormonal contraception: follow-up study, Denmark 2001-10". BMJ 344: 1–9. doi:10.1136/bmj.e2990. PMID 22577198.
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