Reference for Nedarim 65:9

<big><strong>גמ׳</strong></big> אלמא אברוחי ארי בעלמא הוא ושרי

<b><i>MISHNAH</i></b>. AND WHATEVER IS NOT EMPLOYED IN THE PREPARATION OF FOOD, WHERE SUCH ARE HIRED OUT, IT IS FORBIDDEN.<span class="x" onmousemove="('comment',' Even to one who is under a vow in respect of food as explained in the Gemara above, for the remission of the hiring fee is a benefit leading to the enjoyment of food. ');">⁹</span>

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