Kaleńska-Rodzaj, J. “Motivation in Learning to Play Musical Instrument. The Use of the Expectancy-Value Model of Achievement-Related”. Annales Universitatis Paedagogicae Cracoviensis Studia Psychologica, vol. 7, no. 1, Dec. 2014, pp. 8-23, https://studia-psychologica.uken.krakow.pl/article/view/5599.