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Dawood FS, Iuliano AD, Reed C, et al. (septembar 2012). „Estimated global mortality associated with the first 12 months of 2009 pandemic influenza A H1N1 virus circulation: a modelling study”. The Lancet. Infectious Diseases. 12 (9): 687—95. PMID22738893. doi:10.1016/S1473-3099(12)70121-4.
CDC (28. 2. 2020). „Weekly U.S. Influenza Surveillance Report (FluView)”. Centers for Disease Control and Prevention (на језику: енглески). Архивирано из оригинала 01. 03. 2020. г. Приступљено 1. 3. 2020.CS1 одржавање: Неподобан URL (веза)