Reference for Gittin 151:6

איכא דאמרי לרבנן קאמר להו והכי קאמר להו אין לך תנאי בכתובים שאינו כפול וגמרינן מינייהו

This is the view of R. Meir. The Sages, however, say that if the condition is fulfilled it is a Get and if not it is no Get. Rabban Simeon b. Gamaliel says: There is no condition in the Scriptures which is not duplicated.<span class="x" onmousemove="('comment',' E.g., Gen. XXIV, 3ff.; Num. XIX, V, 19ff.; Is., I, 19, 20. ');">⁵</span>

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