Reference for Eruvin 113:8

במתא עיגולתא והא ריבעוה אימור דאמרינן חזינן כמאן דמרבעא רבועי ודאי מי מרבענא

Consequently you must admit that by 'round about' was meant round about the corners; well then, here also by 'round about' was meant round about the corners. Said R'Habibi<span class="x" onmousemove="('comment',' MS.M 'Aha'; Rashi (s.v. a.l.) 'Habiba'.');">¹³</span> of Hoza'ah<span class="x" onmousemove="('comment',' The modern Khuzistan.');">¹⁴</span>

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