Thus following, I saw my patron and master [Lord Śrī Kṛṣṇa] sitting alone and deeply thinking, taking shelter on the bank of the river Sarasvatī although He is the shelter of the goddess of fortune.
Srimad Bhagavata Purana
श्रीमद्भागवतमहापुराणम्
मूल श्लोकः
अद्राक्षमेकमासीनं विचिन्वन् दयितं पतिम् । श्रीनिकेतं सरस्वत्यां कृतकेतमकेतनम्
adrākṣamekamāsīnaṃ vicinvan dayitaṃ patim | śrīniketaṃ sarasvatyāṃ kṛtaketamaketanam
SB 3.4.6