Surya Siddhanta
भूवृत्तपादविवरास् ताश् चान्योन्यम् प्रतिष्ठिताः। ताभ्यश् चोत्तरगो मेरुस् तावान् एव सुराश्रयः॥
These cities are situated at an equal distance from each other on each quarter of earth’s equator. At an equal distance from them, to the north is situated the Uttara Meru, the abode of the demigods (sura).
english translation