Reference for Shabbat 276:12

ומאי ישוטטו לבקש את דבר ה' אמרו עתידה אשה שתטול ככר של תרומה ותחזור בבתי כנסיות ובבתי מדרשות לידע אם טמאה היא ואם טהורה היא ואין מבין

Rab said: They learnt this only of two men; but [if done] by one man, it is forbidden.<span class="x" onmousemove="('comment',' Rashi: two men do not stretch it well; but one person is forced to tie one end to a stake, stretch it, and then tie the other end to another stake, whereby it becomes a tent. Rashi however is dissatisfied with this explanation and states that he does not understand it, nor are other commentators more satisfactory. ');">¹¹</span>

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