Protz, Roger (2004). „The Complete Guide to World Beer”. Архивирано из оригинала 12. 10. 2016. г. Приступљено 26. 06. 2019. „When people of the ancient world realised they could make bread and beer from grain, they stopped roaming and settled down to cultivate cereals in recognisable communities.”
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Cheney, Ralph (јул 1947). „The Biology and Economics of the Beverage Industry”. Economic Botany. 1 (3): 243—275. JSTOR4251857. doi:10.1007/bf02858570.
Protz, Roger (2004). „The Complete Guide to World Beer”. Архивирано из оригинала 12. 10. 2016. г. Приступљено 26. 06. 2019. „When people of the ancient world realised they could make bread and beer from grain, they stopped roaming and settled down to cultivate cereals in recognisable communities.”