Reference for Bekhorot 119:6

אברור עשרה ואטול מהן אחד והשאר פטורין

- R'Huna B'Sehorah explained this before Rab on [the Sabbath preceding] a Festival:<span class="x" onmousemove="('comment',' When the laws of the forthcoming Festival were being expounded.');">⁴</span>

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