Reference for Eruvin 50:1

אי דעבידא כי אכסדרה הכי נמי הב"ע דעבדה כי אורזילא

- If [the roof<span class="x" onmousemove="('comment',' V. Rashi. Aliter: The walls in the covered area (v. Tosaf. s.v. a.l.) .');">¹</span> over the beth se'ah] were made like an exedra<span class="x" onmousemove="('comment',' I.e., level and not slanting (Rashi) . Aliter: Open on two sides only (v. Tosaf. l.c.) .');">²</span> [the ruling would] indeed have been the same,<span class="x" onmousemove="('comment',' Sc. even Rabbah would adopt the ruling of Rab.');">³</span>

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