Reference for Avodah Zarah 128:11

שמנו כיינו ס"ד שמן מי קא הוי יין נסך אלא יינו כשמנו

And his oil is like his wine. (How can it enter your mind to say that his oil is like his wine; can oil become yayin nesekh)! Rather his wine is like his oil.

Jastrow