http://www.cmha.ca/mental-health/understanding-mental-illness/depression/
http://www.helpguide.org/articles/depression/depression-signs-and-symptoms.htm
http://www.brainyquote.com/quotes/keywords/depression.html
http://www.dbsalliance.org/site/PageServer?pagename=education_statistics_depression
http://www.webmd.com/depression/guide/depression-types
http://www.helpguide.org/articles/depression/depression-signs-and-symptoms.htm
http://www.brainyquote.com/quotes/keywords/depression.html
http://www.dbsalliance.org/site/PageServer?pagename=education_statistics_depression
http://www.webmd.com/depression/guide/depression-types