Reference for Yoma 91:1

אבל מהאי גיסא ומהאי גיסא אימא לא צריכא

but not to one side or to the other,<span class="x" onmousemove="('comment',' Though it is on the western side of the altar.');">¹</span> therefore it was necessary [to have both phrases].

Jastrow

Jastrow