Reference for Niddah 89:18

לתני פחות מכאן ולא כלום מאי לאו הא קמ"ל

Rather the practical difference is the case, for instance, where her husband had intercourse with her while she was under<span class="x" onmousemove="('comment',' Lit., 'within'. ');">¹⁵</span>

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