Mohamed Zasfirul bin Zainal Abidin. (2010). The proficiency and perceptions of English among top management staff in Malaysia. Kulliyyah of Islamic Revealed Knowledge and Human Sciences, International Islamic University Malaysia.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Mohamed Zasfirul bin Zainal Abidin. The Proficiency and Perceptions of English Among Top Management Staff in Malaysia. Gombak, Selangor: Kulliyyah of Islamic Revealed Knowledge and Human Sciences, International Islamic University Malaysia, 2010.
توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)Mohamed Zasfirul bin Zainal Abidin. The Proficiency and Perceptions of English Among Top Management Staff in Malaysia. Kulliyyah of Islamic Revealed Knowledge and Human Sciences, International Islamic University Malaysia, 2010.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.