The Natural History of Pliny, tr. John Bostock, Henry Thomas Riley, London: Bell, 1856–93, Volume 3, p. 84: "It is a remarkable circumstance, that the barbarous nations which subsist on milk have been for so many ages either ignorant of the merits of cheese, or else have totally disregarded it; and yet they understand how to thicken milk and form therefrom an acrid kind of milk with a pleasant flavour".
"தயிர்". University of Madras Tamil Lexicon. Universiti Madras. 2015. m/s. 1759. Dicapai pada 1 Julai 2021 – melalui Digital Dictionaries of South Asia.
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Nummer, Brian A. "Fermenting Yogurt at Home". National Center for Home Food Preservation. Dicapai pada 8 January 2013.
