Reference for Chullin 244:15

לימדתנו רבינו אלו שעורותיהן כבשרן ועור הראש של עגל הרך

stated in the name of R'Simeon, [If a man while slaughtering a burnt-offering intended to burn] either the skin around the hoofs, or the skin of the head of a young calf, or the skin from under the fat tail, or any of the skins<span class="x" onmousemove="('comment',' This Tanna - Eleazar b. Judah - is of the opinion that all the skins mentioned in our Mishnah are edible and therefore regarded as flesh, whereas the first Tanna (with whom R. Johanan is in agreement) considers only the skin under the fat tail as edible.');">⁹</span>

Jastrow