Mohd Mustafa Izahar. (2006). Analysis of errors in subject-verb agreement in English language written compositions among post-graduate teacher trainees. Fakulti Sains Sosial Dan Kemanusiaan, Universiti Kebangsaan Malaysia.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Mohd Mustafa Izahar. Analysis of Errors in Subject-verb Agreement in English Language Written Compositions Among Post-graduate Teacher Trainees. Bangi: Fakulti Sains Sosial Dan Kemanusiaan, Universiti Kebangsaan Malaysia, 2006.
توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)Mohd Mustafa Izahar. Analysis of Errors in Subject-verb Agreement in English Language Written Compositions Among Post-graduate Teacher Trainees. Fakulti Sains Sosial Dan Kemanusiaan, Universiti Kebangsaan Malaysia, 2006.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.