Reference for Chullin 252:5

והיכן מגעו עם אחת מהן

A barley's bulk of bone conveys uncleanness by carrying and by contact but not by overshadowing;<span class="x" onmousemove="('comment',' This is a traditional law and not derived from the exposition of a verse, but v. Tosaf. s.v. , and s.v. .');">⁴</span>

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