Reference for Pesachim 91:10

א"ר אבהו אמר רבי שמעון בן לקיש לגבל ולתפלה ולנטילת ידים ארבעה מילין

IT IS FORBIDDEN. <big><b>GEMARA: </b></big>What if there is no [dough] similar to it? - Said R'Abbahu in the name of R'Simeon B'Lakish: [The period for fermentation is] as long as it takes a man to walk from the Fish Tower [Migdal Nunia] to Tiberias, which is a mil.<span class="x" onmousemove="('comment',' Two thousand cubits. This is generally regarded as an eighteen minutes' walk. If it is eighteen minutes since the dough was kneaded (before being set in the oven) , it is leaven.');">¹¹</span>

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