Medical News Today. https://www.medicalnewstoday.com/articles/322159.php
Diakses 12 Februari 2019Science Daily. https://www.sciencedaily.com/releases/2018/06/180614212658.htm
Diakses 12 Februari 2019Everyday Health. https://www.everydayhealth.com/depression-pictures/depression-symptoms-to-watch-for.aspx
Diakses 12 Februari 2019 Reviewed by dr. Reni