Reference for Chullin 275:33

כל חד וחד בתר גיזה נפקא לה מרשותיה

Who is the authority that holds that where the seller keeps back some for himself we turn to the seller?<span class="x" onmousemove="('comment',' I.e., the obligation to give the first of the fleece to the priest lies entirely upon the seller.');"><sup>22</sup></span>