Reference for Bava Kamma 38:3

יתיב רבי יהודה נשיאה ורבי אושעיא אקילעא דרבי יהודה נפק מילתא מבינייהו כשכשה בזנבה מהו א"ל אידך וכי יאחזנה בזנבה וילך אי הכי קרן נמי נימא וכי יאחזנה בקרן וילך

R. Judah [II] the Prince and R. Oshaia had both been sitting near the entrance of the house of R. Judah, when the following matter was raised between them: In the case of an animal knocking about with its tail, [and doing thereby damage on public ground] what would be the law? — One of them said in answer: Could the owner be asked to hold the tail of his animal continuously wherever it goes?<span class="x" onmousemove="('comment',' There will therefore be no liability. ');">²</span>

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