Reference for Keritot 29:52

איתיביה אביי לרבה

Now, should you be right in saying that R'Eliezer's reason is because two acts were performed, why should he be exempt here! - Said Mar the son of Rabana: I and Rab Nihumi B'Zechariah have explained this: Here<span class="x" onmousemove="('comment',' Viz., the statement of R. Eliezer that one is guilty for a derivative when performed with its principal act.');">³¹</span>

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