Reference for Bava Metzia 204:7

ושמואל אמר בבא באמצע חדש עסקינן אבל בא בתחלת חדש כוליה למשכיר בא בסוף חדש כוליה לשוכר

— If from there, I might have thought that [the second term] defines the first;<span class="x" onmousemove="('comment',' I.e., an istera, for which I will accept 100 light-weight ma'ahs, so that they are only worth an istera. In that case, the second term is binding because it defines the first. ');">⁵</span>

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