Siricharoen, Aroonrung, and Raksangob Wijitsopon. “A Corpus-Based Comparative Study of Lexical Bundles in Authentic and Textbook English Business Emails”. LEARN Journal: Language Education and Acquisition Research Network 13, no. 2 (July 1, 2020): 41–63. Accessed May 5, 2024. https://so04.tci-thaijo.org/index.php/LEARN/article/view/243690.