Reference for Bekhorot 53:11

תרומת חוצה לארץ אין בה משום כהן המסייע בבית הגרנות

Samuel said: Terumah from abroad is neutralized in a larger quantity.<span class="x" onmousemove="('comment',' One measure of terumah is nullified in two of hullin, and it is not required that the one measure of terumah should be neutralized in a hundred, as is the case with terumah in the Holy Land. Also, after being neutralized, the whole mixture may be eaten by a non-priest or by the priest himself in his days of levitical impurity.');">⁹</span>

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