Reference for Bekhorot 33:62

הכל מודים שאין צמרו מטמא בנגעים שנאמר

in the other, its smell has not altered.<span class="x" onmousemove="('comment',' The training flax over a shrub does not alter its smell and, moreover, in the latter case a change in its smell is immaterial.');">³³</span>

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