Reference for Nedarim 53:4
אי לרבה רישא רבי עקיבא וסיפא דברי הכל אי לרבא סיפא רבנן ורישא דברי הכל:
Which Tanna is the authority for the following dictum of the Rabbis? If one vowed simultaneously not to benefit from five men, if he is absolved in respect of one of them, he is absolved in respect of all; but [if he stated,] 'Except one of them,' that one is permitted, but the others are forbidden [to him]. According to Rabbah, the first clause agrees with R. Akiba [only], and the second clause with all.<span class="x" onmousemove="('comment',' In the first clause it is assumed that his partially revoking statement was, 'Had I known that X was in the group, I would have said, " a,="" b,="" c,="" etc.="" be="" forbidden,="" but="" x="" permitted".'="" this="" assumption="" is="" based="" on="" the="" contrast="" with="" second="" clause,="" where="" one="" was="" excluded,="" from="" which="" it="" assumed="" that="" his="" revoking="" statement="" was,="" 'had="" i="" known …="" would="" have="" declared,="" "all="" of="" you="" forbidden="" etc."'="" ');"=""><sup>3</sup></span>