1. Ferlay J, Soerjomataram I, Ervik M, Dikshit R, Eser S, Mathers C, Rebelo M, Parkin DM, Forman D, Bray F. GLOBOCAN 2012 v1.0, Cancer Incidence and Mortality Worldwide: IARC CancerBase No. 11 [Internet]. Lyon: International Agency for Research on Cancer; 2013. Available from http://globocan.iarc.fr . Accessed 10 July 2015
2. WHO. International Agency for research on cancer. Latest world cancer statistics. 2013. No. 223 Available on: http://www.iarc.fr/en/media-centre/pr/2013/pdfs/pr223_E.pdf Accessed 10 Aug 2015.
3. Bray F, Ren JS, Masuyer E, Ferlay J. Global estimates of cancer prevalence for 27 sites in the adult population in 2008. Int J Cancer. 2013;132(5):1133–45.
4. Parkin DM, Bray F, Ferlay J. Global cancer statistics. CA Cancer J Clin. 2005;55:74–108.
5. Bruni L, Barrionuevo-Rosas L, Albero G, Aldea M, Serrano B, Valencia S, et al. ICO Information Centre on HPV and Cancer (HPV Information Centre). Human Papillomavirus and related diseases in Ethiopia. 2016. Available on: http://www.hpvcentre.net/statistics/reports/XWX.pdf .