1. SpringerBriefs in Education,2019
2. Piaget J (1972) Psychology and epistemology: towards a theory of knowledge. Penguin, Harmondsworth
3. Keegan (ed) (1993) Theory of transactional distinction. In Theoretical principles of distinction education. Routledge, London and New York
4. Vygotsky LS (1931) Istoriya razvitija vyshikh psikhicheskih funkcii. In Matjushkina AM (ed) Sobranije Sochinenii. Tom 3. Problemy razvitija psihiki. Pedagogika, Moscow
5. Moore MG (ed) (2019) Handbook of distance education, 4th edn. Routledge, New York