"How flu vaccine effectiveness and efficacy are measured". Centers for Disease Control and Prevention, National Center for Immunization and Respiratory Diseases, US Department of Health and Human Services. 2016-01-29. Retrieved 2020-05-06.
Weinberg, Geoffrey A.; Szilagyi, Peter G. (2010-06-01). "Vaccine Epidemiology: Efficacy, Effectiveness, and the Translational Research Roadmap". The Journal of Infectious Diseases. 201 (11): 1607–1610. doi:10.1086/652404. ISSN0022-1899. PMID20402594. S2CID29528780.
Weinberg, Geoffrey A.; Szilagyi, Peter G. (2010-06-01). "Vaccine Epidemiology: Efficacy, Effectiveness, and the Translational Research Roadmap". The Journal of Infectious Diseases. 201 (11): 1607–1610. doi:10.1086/652404. ISSN0022-1899. PMID20402594. S2CID29528780.
Weinberg, Geoffrey A.; Szilagyi, Peter G. (2010-06-01). "Vaccine Epidemiology: Efficacy, Effectiveness, and the Translational Research Roadmap". The Journal of Infectious Diseases. 201 (11): 1607–1610. doi:10.1086/652404. ISSN0022-1899. PMID20402594. S2CID29528780.
Weinberg, Geoffrey A.; Szilagyi, Peter G. (2010-06-01). "Vaccine Epidemiology: Efficacy, Effectiveness, and the Translational Research Roadmap". The Journal of Infectious Diseases. 201 (11): 1607–1610. doi:10.1086/652404. ISSN0022-1899. PMID20402594. S2CID29528780.