Reference for Nedarim 41:3

רבא אמר אפילו תימא רבנן מי קתני שניהן רצו שניהן רוצין קתני

Which Tanna holds this view? — R. Judah, who said on the authority of R. Tarfon: Neither is a <i>nazir</i>, because neziroth must be expressed with certainty.<span class="x" onmousemove="('comment',' 19b. Thus here too, in the case of the incentive vow, since the two parties are dependent upon another, the vow is invalid. ');">³</span>

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