(2008). The employees that laugh together..: How laughter can increase profitability. Enterprise.
Chicago-referens (17:e uppl.)"The Employees That Laugh Together..: How Laughter Can Increase Profitability." Enterprise 2008.
MLA-referens (9:e uppl.)"The Employees That Laugh Together..: How Laughter Can Increase Profitability." Enterprise, 2008.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.