Reference for Chullin 164:21

אין קסבר אכל שני זיתי חלב בהעלם אחד חייב שתי חטאות

Whence [do you gather this]? - From the following: It was taught: If a person sowed diverse kinds, diverse kinds, he incurs stripes.<span class="x" onmousemove="('comment',' V. Lev. XIX, 19. Apparently he sowed diverse kinds of seeds on two occasions.');">⁹</span>

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