Surya Siddhanta
शिलातले +अम्बुसम्शुद्धे वज्रलेपे +अपि वा समे। तत्र शङ्क्वङ्गुलैर् इष्टैः समम् मण्डलम् आलिखेत् ॥
On the surface of a stone levelled with water or on the levelled floor of chunam work, describe a circle with a radius of a certain number of digits.
english translation
zilAtale +ambusamzuddhe vajralepe +api vA same। tatra zaGkvaGgulair iSTaiH samam maNDalam Alikhet ॥
hk transliteration by Sanscript