Surya Siddhanta
ततः समन्तात् परिधिः क्रमेणायम् महार्णवः। मेखलेव स्थितो धात्र्या देवासुरविभागकृत्॥
Surrounding it on every side is fixed next this great ocean, like a girdle about the earth, dividing the two hemispheres of the gods and of the demons.
english translation