@misc{Mazur_Zofia_Music,
 author={Mazur, Zofia and Łaguna, Mariola},
 howpublished={online},
 publisher={Educational Research Institute},
 language={pol},
 type={article},
 title={Music performance achievement in instrumental performance: definitions, assessment criteria, measurement tools},
 keywords={music performance achievement, musical attainment, instrumental performance, musical education, measurement},
}