Greiner, K. R. (2000). A study of academic service quality and instructional quality in a Midwestern Higher Education environment. Drake University.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Greiner, Keith Roger. A Study of Academic Service Quality and Instructional Quality in a Midwestern Higher Education Environment. Des Moines: Drake University, 2000.
توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)Greiner, Keith Roger. A Study of Academic Service Quality and Instructional Quality in a Midwestern Higher Education Environment. Drake University, 2000.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.