D. Hajdú, „The impact of population processes on adult training in Borsod-Abaúj-Zemplén County between 2010 and 2019“, Studia Mundi – Economica, Bd. 8, Nr. 3, S. 131–142, Sep. 2021, doi: 10.18531/Studia.Mundi.2021.08.03.131-142.