Reference for Shevuot 35:10

אמר מר פירש מיד חייב היכי עביד אמר רב הונא משמיה דרבא נועץ עשר צפרניו בקרקע עד שימות וטוביה

since it has been taught with reference to it:<span class="x" onmousemove="('comment',' As a comment on Mishnah in Nid. 14a.');">²³</span> This is the positive precept concerning a menstruous woman for which one is liable; and if it is [as you say],<span class="x" onmousemove="('comment',' That it refers to entering.');">²⁴</span> it is a negative precept!<span class="x" onmousemove="('comment',' Lev. XVIII, 19.');">²⁵</span>

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