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Chain 1909, "No longer in popular use, Geʽez has always remained the language of the Church". Chain, M. (1909). "Ethiopia". The Catholic Encyclopedia. Vol. V. New York: Robert Appleton Company. Archived from the original on 2007-02-06.
Chain 1909, "No longer in popular use, Geʽez has always remained the language of the Church". Chain, M. (1909). "Ethiopia". The Catholic Encyclopedia. Vol. V. New York: Robert Appleton Company. Archived from the original on 2007-02-06.
Pankhurst 1968, pp. 666f; cf. the EOTC's own account at its official website. "Church Teachings". Retrieved from the Internet Archive on March 12, 2014. Pankhurst, Richard K. P. (1968). An Economic History of Ethiopia, 1800–1935. Addis Ababa: Haile Selassie I University Press.