Siahpour, M., F. Rahimi, and E. Sharifzadeh. “The Effect of Watching Documentary Videos With L1 or L2 Subtitles on Iranian learners’ Vocabulary Learning”. Contemporary Educational Researches Journal, vol. 12, no. 3, June 2022, pp. 142–152, doi:10.18844/cerj.v12i3.6810.