The Bible Ezekiel 4:12 And you shall eat it as barley cakes, and you shall bake it with dung that comes out of man. http://bibleapps.com/ezekiel/4-12.htm
Picornell Gelabert, Llorenç; Asouti, Eleni; Martí, Ethel Allué (2011). "The ethnoarchaeology of firewood management in the Fang villages of Equatorial Guinea, central Africa: Implications for the interpretation of wood fuel remains from archaeological sites". Journal of Anthropological Archaeology. 30 (3): 375–384. doi:10.1016/j.jaa.2011.05.002. ISSN0278-4165.
Picornell Gelabert, Llorenç; Asouti, Eleni; Martí, Ethel Allué (2011). "The ethnoarchaeology of firewood management in the Fang villages of Equatorial Guinea, central Africa: Implications for the interpretation of wood fuel remains from archaeological sites". Journal of Anthropological Archaeology. 30 (3): 375–384. doi:10.1016/j.jaa.2011.05.002. ISSN0278-4165.