Reference for Menachot 81:12

ופליגא דמלאכא דמלאכא אשכחי' לרב קטינא דמיכסי סדינא אמר ליה קטינא קטינא סדינא בקייטא וסרבלא בסיתוא ציצית של תכלת מה תהא עליה

Is not this obvious? - It is necessary to be stated where it was only fastened down with pins.<span class="x" onmousemove="('comment',' In this case all agree that it is subject to zizith, since the pins fasten the parts firmly together, and there is little likelihood of the garment becoming unfolded.');">⁸</span>

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