Surya Siddhanta
अन्ये +अपि समसूत्रस्था मन्यन्ते +अधः परस्परम् । भद्राश्वकेतुमालस्था लङ्कासिद्धपुराश्रिताः॥
Others, too, who are situated upon the same diameter (samasMrastha) , think one another underneath—as the dwellers in Bhadracva and in Ketumala, and the inhabitants of Lanka and of the city of the Perfected, respectively.
english translation