Prostate Cancer Foundation. https://www.pcf.org/about-prostate-cancer/what-is-prostate-cancer/prostate-cancer-causes/
Diakses pada Mei 2019Cancer.org. https://www.cancer.org/cancer/prostate-cancer/detection-diagnosis-staging/signs-symptoms.html
Diakses pada Mei 2019Cancer Research UK. https://www.cancerresearchuk.org/about-cancer/prostate-cancer/risks-causes
Diakses pada Mei 2019