Brihat Parashara Hora Shastra
अथ स्पष्टबलं वक्ष्ये स्थानकालादिसम्भवम् । नीचोनां खचरं भार्धाधिक चक्राद् विशोधयेत् ॥ १॥
Sthan Bal. Firstly Uchch Bal. Now about the strengths by classes positional, temporal etc. Deduct from the longitude of the Grah its (deep) debilitation point. If the sum is less than 6 Rāśis, consider it, as it is; if it exceeds 6 Rāśis, deduct the same from 12 Rāśis. The sum so got be converted into degrees etc. and divided by 3, which is the Grah‟s Uchch Bal in Virupas.
english translation
atha spaSTabalaM vakSye sthAnakAlAdisambhavam । nIconAM khacaraM bhArdhAdhika cakrAd vizodhayet ॥ 1॥
hk transliteration by Sanscript