Philipps, E. (1990). Documentation made easy: A library manual for nongovernmental organizations specializing in appropriate technology and rural development. Friedr, Vieweg & Sohn.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Philipps, Eva. Documentation Made Easy: A Library Manual for Nongovernmental Organizations Specializing in Appropriate Technology and Rural Development. Braunschweig, Wiesbaden: Friedr, Vieweg & Sohn, 1990.
توثيق جمعية اللغة المعاصرة MLA (الإصدار التاسع)Philipps, Eva. Documentation Made Easy: A Library Manual for Nongovernmental Organizations Specializing in Appropriate Technology and Rural Development. Friedr, Vieweg & Sohn, 1990.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.