Reference for Eruvin 187:3

אהדרינהו רב לאפיה אמר להו שמואל אי קפיד אבא וקטרו בה

For Rab and Samuel were once sitting in a certain courtyard when a parting wall<span class="x" onmousemove="('comment',' Lit., 'which (was) between between'.');">⁴</span> collapsed.<span class="x" onmousemove="('comment',' And the courtyard in which they sat was thus exposed to the adjoining courtyard.');">⁵</span>

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