Anandakanda 2.7.101

2.7.101

maṇḍūro'yaṃ samākhyātaḥ śuddhaṃ ślakṣṇaṃ niyojayet /
gomūtre triphalā kvāthyā tatkvāthe secayecchanaiḥ //

This is described as maṇḍūra; one should employ it clean and fine. / One should decoct the three myrobalans in cow's urine, and slowly quench it in that decoction.