University College of Addis Ababa. Geophysical Observatory & Haile Sellassie I University. Geophysical Observatory. (1959). Bulletin of the Geophysical Observatory. University College Press.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)University College of Addis Ababa. Geophysical Observatory و Haile Sellassie I University. Geophysical Observatory. Bulletin of the Geophysical Observatory. Addis Ababa: University College Press, 1959.
توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)University College of Addis Ababa. Geophysical Observatory و Haile Sellassie I University. Geophysical Observatory. Bulletin of the Geophysical Observatory. University College Press, 1959.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.