Kurmapurana 2.26.19

Kūrmapurāṇa 2.26.19

vaiśākhyāṃ paurṇamāsyāṃ tu brāhmaṇān sapta pañca vā /
upoṣya vidhinā śāntaḥ śuciḥ prayatamānasaḥ //