Skandapurana 5.129.52

5.129.52

yena no yāti pātālaṃ gaṃgā svargaparicyutā ..
tasmāttvaṃ deva madvākyātsvamūrdhnā vaha jāhnavīm ..52..

“So that the Gaṅgā, fallen from heaven, does not go down to Pātāla, / therefore, O Lord, at my request, bear the Jāhnavī on your head!”