Surya Siddhanta
प्राक्पश्चिमाश्रिता रेखा प्रोच्यते सममण्डले । उनण्डले च विषुवन्मण्डले परिकीर्त्यते ॥
The line representing the Prime Vertical, the six o'clock line or the equinoctial, passes through the east and west points of the Horizon.
english translation
prAkpazcimAzritA rekhA procyate samamaNDale । unaNDale ca viSuvanmaNDale parikIrtyate ॥
hk transliteration by Sanscript