Anandakanda 1.23.244

1.23.244

<niśācaramūlikākalpaḥ>
gaṅgāyamunayormadhye prayāgo nāma rākṣasaḥ /
tasyāsane varārohe kṣaṇādbadhyeta sūtakaḥ //

<The procedure using the niśācara plant>
Between the Gaṅgā and the Yamunā is a demon named Prayāga; / upon his seat, O fair-hipped lady, quicksilver is fixed in an instant.