Reference for Bava Batra 304:6

והא אפליגו בה חדא זימנא במתנת שכיב מרע שכתוב בה קנין

But surely their<span class="x" onmousemove="('comment',' Rab and Samuel. ');">¹⁷</span> difference of opinion on the [principle] has [already] once been expressed in [the case of] the [deed of a] gift of a dying man, in which symbolic acquisition was entered!<span class="x" onmousemove="('comment',' Supra 152a top. Why, then, should they express the same principles again? ');">¹⁸</span> [Both are] required. For if [their dispute] had been stated [in connection] with the first case,<span class="x" onmousemove="('comment',' Lit., 'in that', ');">¹⁹</span> [it might have been assumed that] in that [case only] Rab adheres<span class="x" onmousemove="('comment',' Lit., 'said'. ');">²⁰</span>

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