Reference for Eruvin 18:3

ולרבן שמעון בן גמליאל להוי כנראה מבחוץ ושוה מבפנים

But even according to R'Simeon B'Gamaliel<span class="x" onmousemove="('comment',' Granted that the space bordered by the side-post constitutes an alley on its own.');">⁶</span> [why] should [not this alley<span class="x" onmousemove="('comment',' Sc. the space bordered by the side-posts (v. previous note) .');">⁷</span> be permitted]<span class="x" onmousemove="('comment',' Without an extra side-post for itself.');">⁸</span>

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