Surya Siddhanta
ततो ग्राहकखण्डेन प्राग्वन् मण्डलम् आलिखेत् । तद्ग्राह्यमण्डलयुतिर् यत्र तत्र निमीलनम्॥
From that point, with a radius equal to half the eclipsing body, draw a circle, as in the former case : where this meets the circle of the eclipsed body, there immersion takes place.
english translation
tato grAhakakhaNDena prAgvan maNDalam Alikhet । tadgrAhyamaNDalayutir yatra tatra nimIlanam॥
hk transliteration by Sanscript