Stetina, Birgit U., Reinhold Jagsch, Cornelia Schramel, Tamara Lederman Maman, and Ilse Kryspin-Exner. 2008. “Exploring Hidden Populations: Recreational Drug Users”. Cyberpsychology: Journal of Psychosocial Research on Cyberspace 2 (1):Article 4. https://cyberpsychology.eu/article/view/4208.