Karu, K., L. Jõgi, I.-E. Rannala, T. Roosalu, L. Teder, and H. Põlda. “Construction of Meaning of ‘non-Formal learning’ in Policy Documents”. Eesti Haridusteaduste Ajakiri. Estonian Journal of Education, vol. 7, no. 1, May 2019, pp. 50-75, doi:10.12697/eha.2019.7.1.03.