3Fredrickson, B. L. (2004). Gratitude, like other positive emotions, broadens and builds. In : Emmons, R. A. , McCullough, M. E. (Eds.) ,The Psychology of Gratitude . New York: Oxford University Press.
4Watkins P, Woodward K, Stone T, Kolts R L. Gratitude and happiness: Development of a measure of grati- tude, and relationships with subjective well - being [ J ]. Social Behavior and Personality, 2003, 31:431 - 451.
8Rosenberg E L. Levels of analysis and the organization of affeet. Review of General Psychology[ J ], 1998,2: 247 - 270.
9Froh. Jeffrey J, Sefiek. William, Emmons. Robert A. Counting blessings in early adoleseents: An experi- mental study of gratitude and subjective wellbeing. Journal of school Psychology,2008,46, (2).
10Watkins PC,Woodward K, Stone T, Kolts RL. Gratitude and happiness: Development of a measure of grati- tude, and relationships with subjective weUbeing. Social Behavior and Personality,2003,31, (5).