SECRET, I. FOREIGN RESEARCH OF PSYCHOLOGICAL AND PEDAGOGICAL PRINCIPLES OF DISTANCE EDUCATION. Educational Dimension, Kryvyi Rih, Ukraine, v. 20, p. 107–113, 2008. DOI: 10.31812/educdim.6560. Disponível em: https://journal.kdpu.edu.ua/ped/article/view/6560. Acesso em: 17 may. 2024.