↑ "Prehistoric man ate flatbread 30,000 years ago: study". Physorg.com. Agence France-Presse. 19 October 2010. Diakses tanggal 19 October 2010. ↑ McGee, Harold (2004). On food and cooking. Scribner. hlm. 517. ISBN 0-684-80001-2. ↑ Tannahill, Reay (1973). Food in History. Stein and Day. hlm. 68–69. ISBN 0-8128-1437-1. ↑ Pliny the Elder (1938). Natural History. Loeb Classics. hlm. 1.255. Generally however they do not heat it up at all, but only use the dough kept over from the day before; manifestly it is natural for sourness to make the dough ferment, ↑ Chorleywood Industrial Bread Making Process. allotment.org.uk