1. Centers for Disease Control and Prevention Global cancer statistics 2016 http://www.cdc.gov/cancer/international/statistics.htm
2. World Health Organization Liver cancer: Estimated incidence, mortality and prevalence worldwide 2012 http://globocan.iarc.fr/old/FactSheets/cancers/liver-new.asp
3. American Cancer Society Liver cancer 2016 http://www.cancer.org/acs/groups/cid/documents/webcontent/003114-pdf.pdf