Al-Hashash, A. J., & Netusil, A. J. (1981). Investigation of students' study habits under traditional and phase achievement systems of instruction in a college biology course. Iowa State University.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Al-Hashash, Abdullatif Jassim, و Anton J. Netusil. Investigation of Students' Study Habits Under Traditional and Phase Achievement Systems of Instruction in a College Biology Course. Ames: Iowa State University, 1981.
توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)Al-Hashash, Abdullatif Jassim, و Anton J. Netusil. Investigation of Students' Study Habits Under Traditional and Phase Achievement Systems of Instruction in a College Biology Course. Iowa State University, 1981.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.