SB 8.24.45

nibadhya nāvaṁ tac-chṛṅge
 yathokto hariṇā purā
varatreṇāhinā tuṣṭas
 tuṣṭāva madhusūdanam
Word for word: 
nibadhya — anchoring; nāvam — the boat; tat-śṛṅge — onto the horn of the big fish; yathā-uktaḥ — as advised; hariṇā — by the Supreme Personality of Godhead; purā — before; varatreṇa — used as a rope; ahinā — by the great serpent (of the name Vāsuki); tuṣṭaḥ — being pleased; tuṣṭāva — he satisfied; madhusūdanam — the Supreme Lord, the killer of Madhu.
Translation: 
Following the instructions formerly given by the Supreme Personality of Godhead, the King anchored the boat to the fish’s horn, using the serpent Vāsuki as a rope. Thus being satisfied, he began offering prayers to the Lord.