Reference for Pesachim 57:8

רבא אמר לוקה לא יליף רבי יהודה שאור דאכילה משאור דראייה ורב אחא בר יעקב אמר אינו לוקה יליף שאור דאכילה משאור דראייה

[No,] it refers to the first clause, and he states thus: LEAVEN BELONGING TO A GENTILE OVER WHICH PASSOVER HAS PASSED IS PERMITTED FOR USE, BECAUSE IT IS SAID, NEITHER SHALL THERE BE LEAVEN SEEN WITH THEE, [implying] thine own thou must not see, but thou mayest see the leaven of strangers or of the Most High; and se'or of 'eating' is learnt from se'or of 'seeing'. Now they<span class="x" onmousemove="('comment',' Sc. Raba and R. Aha b. Jacob.');">¹¹</span>

Jastrow