1. Center for Disease Control and Prevention (2019) HPV-associated cancer statistics. https://www.cdc.gov/cancer/hpv/statistics/index.htm.
2. Center for Disease Control and Prevention (2019) HPV vaccines: vaccinating your preteen or teen. https://www.cdc.gov/hpv/parents/vaccine.html.
3. National Cancer Institute (2020) HPV and cancer. https://www.cancer.gov/about-cancer/causes-prevention/risk/infectious-agents/hpv-and-cancer.
4. World Health Organization (2018) Cervix uteri fact sheet. International agency for research on cancer. http://gco.iarc.fr/today/data/factsheets/cancers/23-Cervix-Uteri-fact-sheet.pdf
5. ICO/IARC HPV Information Centre (2019) China human papillomavirus and related cancers, fact sheet 2018: HPV Information Centre. https://hpvcentre.net/statistics/reports/CHN_FS.pdf