Valmiki Ramayana Bala Kanda Sarga 42 Shloka 23
Original Shlokaइयं हैमवती गङ्गा ज्येष्ठा हिमवतस्सुता। तां वै धारयितुं शक्तो हरस्तत्र नियुज्यताम्।।1.42.23।।
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हैमवती Haimavati, the daughter of Himavat, इयम् this, गङ्गा Ganga, हिमवत: Himavat's, ज्येष्ठा सुता eldest daughter, ताम् her, धारयितुम् to hold, शक्त: capable, हर: lord Shiva, तत्र there, नियुज्यताम् may be entreated.
'This Hymavati (Ganga) is Himavat's eldest daughter and only lord Siva is capable to hold (the force of her descent to earth). Therefore let Siva be entreated'.