Reference for Eruvin 33:5

ואלא הא דקתני ובלבד שלא יהא בית סאתים פנוי מאי לאו פנוי מאדם לא פנוי מכלים

an area of seven they are permitted<span class="x" onmousemove="('comment',' The carrying of objects on the Sabbath.');">¹⁰</span> even in all the seven;<span class="x" onmousemove="('comment',' Since the unoccupied area is less than two beth se'ah.');">¹¹</span> and if they required only one of five<span class="x" onmousemove="('comment',' For a variant reading, v. Elijah Wilna's glosses.');">¹²</span>

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