Reference for Eruvin 152:10

כי אמרינן ביתא כמאן דמלי דמי הני מילי מן הצד אבל באמצע לא או דילמא לא שנא

- The interpretation is that this refers to the prescribed four handbreadths by four'. R'Abba<span class="x" onmousemove="('comment',' MS.M. 'Raba'.');">²⁵</span> enquired of R'Nahman: If an aperture<span class="x" onmousemove="('comment',' In the roof of a lower room which is the floor of the upper one.');">²⁶</span>

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