Brihat Jataka
लग्नत्रिकोणेषु गुरुस्त्रिभागैर्विकल्प्य वर्षाणि व्योऽनुमानात् ॥ ग्रीष्मोऽर्कलग्ने कथितास्तु शेषैरन्यायनर्तावृतुरर्कचारात् ॥ २६-२ ॥
Having ascertained the years from a guess of the age is Jupiter in the trikonas (1st to 4th, 5th to 8th, or 9th to 12th houses) from the lagna with the three portions (drekkanas), respectively. ॥ The birth was in॥ the summer season when the lagna contains the Sun. But those described with those remaining when the season is in another ayana.
english translation
lagnatrikoNeSu gurustribhAgairvikalpya varSANi vyo'numAnAt ॥ grISmo'rkalagne kathitAstu zeSairanyAyanartAvRturarkacArAt ॥ 26-2 ॥
hk transliteration by Sanscript