IKA RAHMAWATI Y. THE READABILITY LEVEL OF READING TEXTS IN THE ENGLISH LANGUAGE TEXTBOOKS USED BY THE TENTH GRADE. RETAIN : J. Res. Engl. Lang. Teach. [Internet]. 2014 Jul. 8 [cited 2026 Jan. 31];2(3). Available from: https://ejournal.unesa.ac.id/index.php/retain/article/view/8481