GHERBAOUI, Amar. “The Bubble: A Tool for Mastering Spelling in a Heterogeneous Classroom – A Case Study of Second-Year Middle School Students”. El Omda in Linguistics and Discourse Analysis, vol. 2, no. 03, Sept. 2018, pp. 1-17, https://journals.univ-msila.dz/index.php/OLDA/article/view/6959.