Zulkarnain Abdullah. (2000). Attitude of trainee teachers towards problem based learning at the public health institute, Kuala Lumpur.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Zulkarnain Abdullah. Attitude of Trainee Teachers Towards Problem Based Learning at the Public Health Institute, Kuala Lumpur. 2000.
توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)Zulkarnain Abdullah. Attitude of Trainee Teachers Towards Problem Based Learning at the Public Health Institute, Kuala Lumpur. 2000.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.