Reference for Chullin 275:14

אימא מעיל

For it has been taught: Upon the High Priest's head there lay a woollen cap upon which was placed the plate [of gold], in order to fulfil literally what is said: And thou shalt put it on a lace of blue wool!<span class="x" onmousemove="('comment',' Ex. XXVIII, 37.');"><sup>8</sup></span>