SOROKO, N. V. The problem of designing a digital learning ecosystem for massive online courses (Estonian experience). CTE Workshop Proceedings, Kryvyi Rih, Ukraine, v. 4, p. 64–70, 2017. DOI: 10.55056/cte.327. Disponível em: https://acnsci.org/journal/index.php/cte/article/view/327.. Acesso em: 17 feb. 2026.