1. Błędowski, P. & Nowakowska, M. (2010). Podstawy kształcenia ustawicznego [The basics of lifelong learning]. Łódź: Grey Studio Paweł Myszkowski. 143 s. (in Polish)
2. Boiarska-Khomenko, A.V. (2018). Instytualizatsiia osvity doroslykh v Nimechchyni istorychnyi aspekt [The institutionalization of adult education in Germany is a historical aspect]. Osvita doroslykh: teoriia, dosvid, perspektyvy. Kyiv, Nizhyn: Vydavets PP Lysenko M.M. Vyp. 1 (14). s. 103–112. (in Ukrainian)
3. A.V., B.-K. (2019). DEVELOPMENT OF ADULT EDUCATION ISSUES IN THE PEDAGOGICAL THOUGHT OF AUSTRIA. Pedagogical Sciences, (86), 18–21. https://doi.org/10.32999/ksu2413-1865/2019-86-2
4. Die Verfassung des Deutschen Reichs [The Constitution of the German Reich]. (Electronic edition). Retrieved from: https://www.jurion.de/gesetze/wrv/ (in German)
5. Dräger, H. (1984). Historiographie und Geschichte der Erwachsenenbildung [Historiography and history of adult education] / Erwachsenenbildung. Enzyklopädie Erziehungswissenschaft. Stuttgart. Bd. 11. S. 76-92 (in German)