Lerrie Grooten and the group are also writing e-mails to people arround the world with compliments. For more information you can watch the ted talk of shawn achor. They are sending those e-mails for ten years to people. They have spread the idea to a lot of people in the Netherlands by national and local media. People where most of the times really happy to hear about the idea and a lot also start doing this kind of things and it spreads a lot of joy arround the world. For research behind this idea, you can visit the website of Sonja Lyubomirsky and read journal articles about it or listen to radio items of us on the kindness collective Nijmegen youtube account.