Hawwan, Fitra Iqbalul, et al. “The Use of Expressions of Opinion in Written Discussion Text of The Twelfth Year Students of SMA N 1 Ngawen Blora”. Undergraduate Conference on Applied Linguistics, Linguistics, and Literature, vol. 3, no. 1, Sept. 2023, pp. 358-65, https://conference.upgris.ac.id/index.php/allure/article/view/4455.