Freahat، N. M.، و Smadi، O. M. (2012). The appropriateness and difficulty level of the reading content in Action Pack 11, Action Pack 12 and New Headway Plus pre-intermediate as revealed by the content analysis and students' and instructors' perceptions (رسالة دكتوراه غير منشورة). جامعة اليرموك، إربد. مسترجع من http://search.mandumah.com/Record/741005
Freahat، Nasser Mohammad، و Oqlah Mahmoud Smadi. "The Appropriateness and Difficulty Level of the Reading Content in Action Pack 11, Action Pack 12 and New Headway Plus Pre-intermediate As Revealed By the Content Analysis and Students' and Instructors' Perceptions" رسالة دكتوراه. جامعة اليرموك، إربد، 2012. مسترجع من http://search.mandumah.com/Record/741005