Seeing the situation that had been created by the will of the Supreme, the unlimitedly powerful Lord, whose determination is infallible, took the wonderful shape of a tortoise, entered the water, and lifted the great Mandara Mountain.
Srimad Bhagavata Purana
श्रीमद्भागवतमहापुराणम्
मूल श्लोकः
विलोक्य विघ्नेशविधिं तदेश्वरो दुरन्तवीर्योऽवितथाभिसन्धिः । कृत्वा वपुः काच्छपमद्भुतं महत् प्रविश्य तोयं गिरिमुज्जहार
vilokya vighneśavidhiṃ tadeśvaro durantavīryo'vitathābhisandhiḥ | kṛtvā vapuḥ kācchapamadbhutaṃ mahat praviśya toyaṃ girimujjahāra
SB 8.7.8