Reference for Niddah 111:11

חלב שבאשה מטמא טומאת משקין

the uncleanness of liquids but not major uncleanness? — Rather said R. Johanan citing R. Simeon b. Yohai: It<span class="x" onmousemove="('comment',' A fluid that is to be included in the same law of uncleanness as spittle. ');">⁷</span>

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