Healthline. https://www.healthline.com/health/why-does-my-belly-button-smell
Diakses pada 24 Maret 2021Medical News Today. https://www.medicalnewstoday.com/articles/320706
Diakses pada 24 Maret 2021Medicine Net. https://www.medicinenet.com/belly_button/article.htm
Diakses pada 24 Maret 2021