Reference for Eruvin 204:2

ואמר רב שישא בריה דרב אידי סיינא שרי והתניא אסור לא קשיא הא דאית ביה טפח הא דלית ביה טפח

son of R'Idi further stated: A felt cap<span class="x" onmousemove="('comment',' Saiyana, a kind of cap made of felt with a peak projecting above the wearer's forehead.');">⁵</span> is permitted to be worn on the sabbath.<span class="x" onmousemove="('comment',' Though the peak has the shape or appearance of a 'tent'.');">⁶</span> But was it not taught that this<span class="x" onmousemove="('comment',' The wearing of a saiyana on the Sabbath.');">⁷</span> was forbidden? - There is no difficulty, since the latter deals with one whose peak<span class="x" onmousemove="('comment',' Cf. supra n. 1.');">⁸</span>

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