Reference for Menachot 48:4

א"ל וממאי דהאי שאם נגע בו הזב לבתר מדרס דילמא מקמי מדרס דהויא טומאה חמורה על טומאה קלה

If, however, one that had an issue had touched it,<span class="x" onmousemove="('comment',' Before it was used as a curtain. At this stage the sheet bears two kinds of uncleanness: midras uncleanness and the uncleanness from contact with one that had an issue.');">²</span>

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