Yahaya Ibrahim. (1976). A model for an in-service science process workshop for principals, assistant principals and district science supervisors in Malaysia. Southern Illinois University.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Yahaya Ibrahim. A Model for an In-service Science Process Workshop for Principals, Assistant Principals and District Science Supervisors in Malaysia. Carbondale: Southern Illinois University, 1976.
توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)Yahaya Ibrahim. A Model for an In-service Science Process Workshop for Principals, Assistant Principals and District Science Supervisors in Malaysia. Southern Illinois University, 1976.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.