WebMD. https://www.webmd.com/men/rm-quiz-is-my-penis-normal
Diakses pada 23 Mei 2019International Journal of Impotence Research. https://www.nature.com/articles/3901532
Diakses pada 23 Mei 2019British Journal of Urology. https://onlinelibrary.wiley.com/doi/full/10.1046/j.1464-410X.2002.02974.x
Diakses pada 23 Mei 2019.Healthline. https://www.healthline.com/health/erectile-dysfunction/surprising-facts#1
Diakses pada 23 Mei 2019Medical News Today. https://www.medicalnewstoday.com/articles/320748.php
Diakses pada 23 Mei 2019Mental Floss. http://mentalfloss.com/article/32042/corn-flakes-were-invented-part-anti-masturbation-crusade
Diakses pada 18 Juni 2019