Falkenberg, H.K., Johansen, T.R. and Thorud, H.-M.S. (2020) “Headache, eyestrain, and musculoskeletal symptoms in relation to smartphone and tablet use in healthy adolescents ”, Scandinavian Journal of Optometry and Visual Science, 13(2), pp. 8–14. doi:10.5384/sjovs.vol13i2p8-14.