Garudapurana 1.105.32

1.105.32

payasā vāpi māsena parākeṇāpi vā punaḥ /
ṛṣabhaikaṃ sahasraṃ gā dadyātkṣattravadhe pumān //

or by [living on] milk for a month, or by the Parāka observance. / For killing a Kṣatriya, a man should give one bull and a thousand cows;