New Study Shows We Work Harder When We are Happy. Warwick University press release. March 2014. URL:
74
Dolan P. Happiness By Design. Avery, 2014.
75
URL:
76
URL:
77
URL:
78
Shakya H. B., Christakis N. A. A New, More Rigorous Study Confirms: The More You Use Facebook, the Worse You Feel // Harvard Business Review. 2017. 10 April.
