ROZGONJUK, Dmitri, Valdur ROSENVALD, Sven JANNO and Karin TÄHT. Developing a Shorter Version of the Estonian Smartphone Addiction Proneness Scale . Cyberpsychology: Journal of Psychosocial Research on Cyberspace. 2016, vol. 10, no. 4, p. Article 4. DOI: 10.5817/CP2016-4-4