SB 8.5.10
payodhim yena nirmathya
suranam sadhita sudha
bhramamano ’mbhasi dhrtah
kurma-rupena mandarah
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
By churning the Ocean of Milk, Ajita produced nectar for the demigods. In the form of a tortoise, He moved here and there, carrying on His back the great mountain known as Mandara.