Anandakanda 1.15.63

1.15.63

samāharetkṛtasnāno maunī mantraṃ samuccaran /
oṃ amṛtodbhavāya amṛtaṃ kuru kuru svāhā hrīṃ saḥ /
mantraṃ dvādaśasāhasraṃ puraścaryāṃ samācaret //

Having bathed, silent, uttering the mantra, he should gather it: / “Oṃ to the Nectar-Born, make nectar, make nectar, svāhā hrīṃ saḥ!” / One should perform a preliminary repetition of twelve thousand of this mantra.