Saurapurana 9.22

9.22

vaiśākhe śuklapakṣasya tṛtīyā'kṣayasaṃjñitā
tasyāṃ tithau saṃyatātmā brāhmaṇāyā''hitāgnaye

In Vaiśākha, the third day of the bright fortnight is called Akṣayā. / On that lunar day, self-controlled, to a brāhmaṇa who maintains the sacred fire,