Surya Siddhanta
त्रिचतुः कर्णयुत्याप्तास् ते द्विघ्नास् त्रिज्यया हताः। स्फुटाः स्वकर्णास् तिथ्याप्ता भवेयुर् मानलिप्तिकाः॥
These, divided by the sum of radius and the fourth hypothenuse, multiplied by two, and again multiplied by radius, are the respective corrected (sphuta) diameters : divided by fifteen, they are the measures (mdna) in minutes.
english translation
tricatuH karNayutyAptAs te dvighnAs trijyayA hatAH। sphuTAH svakarNAs tithyAptA bhaveyur mAnaliptikAH॥
hk transliteration by Sanscript