15A4/1.4.6, the sixth discourse of the Aṅguttara Nikāya's Cakkavagga: the brahmin Doṇa follows the wheel-marked footprints to the Bhagavā and asks whether he could be a god, a gandhabba, a yakkha or a human being; the Bhagavā answers that the defilements that would make him any of these are destroyed, and that he is a Buddha.
