Brihat Parashara Hora Shastra
स्वच्चशुद्धौ ग्रहः शोध्यः षड्भादूनो भमण्ड्लात् । स्वपिण्डगुणितो भक्तो भादिमानेन वत्सराः ॥ ८॥
If the product is less than 6 Rāśis, deduct it again from 12 Rāśis. The product concerned should be multiplied by the number of years allotted to the Grah and divided by 12 to get the Grah‟s actual contribution.
english translation
svaccazuddhau grahaH zodhyaH SaDbhAdUno bhamaNDlAt । svapiNDaguNito bhakto bhAdimAnena vatsarAH ॥ 8॥
hk transliteration by Sanscript