Matsya Purana 48.64

48.64

pravīṇānṛṣidharmmasya ceśvarān brahmavādinaḥ.
vidvān pratyakṣadharmāṇāṃ buddhimān vṛttimān śucīn.. 48.64 ..

King Bali, seeing the Śudra sons, Kâkṣîvâna, etc., so well up in saintly precepts, so illustrious, so sacred and so versed in saintly lore, said to Dîrghatamâ that they were his sons. The sage said they were not the sons of Bali and claimed them to be his own, on account of their having been born of the Śudra nurse sent by the queen, who herself had discarded him on account of his age and blindness.—63-66.