Rozgonjuk, D., V. Rosenvald, S. Janno, and K. Täht. “Developing a Shorter Version of the Estonian Smartphone Addiction Proneness Scale ”. Cyberpsychology: Journal of Psychosocial Research on Cyberspace, vol. 10, no. 4, Dec. 2016, p. Article 4, doi:10.5817/CP2016-4-4.