Reference for Arakhin 14:15

אמר רב

Levi taught in accord with Rab and he also taught in accord with R'Nahman B'Isaac.<span class="x" onmousemove="('comment',' Levi had an ancient Baraitha the view of which accorded with Rab and another with R. Nahman b. Isaac.');">⁸</span>

Jastrow