Thankful for the little things: A meta-analysis of gratitude interventions
Journal of Counseling Psychology (2016) - Comment
pubmed: 26575348  doi: 10.1037/cou0000107  issn: 0022-0167  issn: 1939-2168 

Don E. Davis, Elise Choe, Joel Meyers, Nathaniel Wade, Kristen Varjas, Allison Gifford, Amy Quinn, Joshua N. Hook, Daryl R. Van Tongeren, Brandon J. Griffin, Everett L. Worthington