Matsyapurana 101.49

101.49

yaścobhayamukhīṃ dadyāt prabhūtakanakānvitām
dinaṃ payovratastiṣṭhet sa yāti paramaṃ padam
etaddhenuvrataṃ nāma punarāvṛttidurlabham //

One who lives on milk in course of the day, and gives away a two-faced (ûbhaimukhî) cow (i.e., half delivered of her calf) made of a big lump of gold, attains the highest bliss. This is (28) Dhenu-Vrata, which makes re-birth almost impossible.—49.