Grühl, M. (1932). The citadel of Ethiopia: The empire of the divine emperor. Cape.
芝加哥风格引文Grühl, Max. The Citadel of Ethiopia: The Empire of the Divine Emperor. London: Cape, 1932.
MLA引文Grühl, Max. The Citadel of Ethiopia: The Empire of the Divine Emperor. Cape, 1932.
警告：这些引文格式不一定是100％准确.