@article {1199, title = {CONTENTS}, journal = {Problems of Education in the 21st Century}, volume = {77}, year = {2019}, month = {April/2019}, pages = {Continuous}, type = {Other}, chapter = {171}, abstract = {Contents, PEC, Vol. 77, No. 2, 2019}, keywords = {contents}, issn = {1822-7864}, url = {http://oaji.net/articles/2019/457-1556863363.pdf}, author = {Editorial Board} }