Shatapatha Brahmana 9.4.1.13

9.4.1.13

atha rathaśīrṣe juhoti | eṣa vai sa sava etadvai tatsūyate yamasmai tametā devatāḥ savamanumanyante yābhiranumataḥ sūyate yasmai vai rājāno rājyamanumanyante sa rājā bhavati na sa yasmai nājyena pañcagṛhītena tā u pañcaivāhutayo hutā bhavanti tasyokto bandhuḥ

He then makes an offering on the Head of the Chariot;--this, indeed, is that very rite of consecration,--and by that he is now consecrated,--which this (Sacrificer) is permitted to perform by those deities with whose permission he is consecrated; for he alone becomes king whom the (other) kings allow (to assume) the royal dignity, and not he whom (they do) not (allow to assume it). With ghee taken in five ladlings (he offers), and this is offered as five oblations: the significance of this has been explained.