External quality assesment of medical laboratories: requirement of MKS EN ISO 15189:2013 - Tosheska Trajkovska, Katerina; Kostovska Irena; Cekovska, Svetlana; Labudovikj, Danica; Bogdanska, Jasna; Brezovska Kavrakova, Julijana; Topuzovska, Sonja (Elsevier, 2022)