Brihat Jataka
स्वोच्चसुहृत्स्वत्रिकोणनवांशै: स्थानबलं स्वगृहोपगतैश्च ॥ दिक्षु बुधाङ्गिरसौ रविभौमौ सूर्यसुत: सितशीतकरौ च ॥ २-१९ ॥
A planet loeated in its sign of exaltation, in a friendly sign, in its own mool trikon sign or in its own sign is considered as endowed with positional strength. Mercury and Jupiter if located in the ascendant get directional strength. This type of strength is got by Sun and Mars when they happen to be located in the 10th house. Saturn is endowed with directional strength if it occupies the 7th house. Similarly Venus and Moon when si tuated in t he 4th house of any bi rth cha rt g et d irectional strength.
english translation
svoccasuhRtsvatrikoNanavAMzai: sthAnabalaM svagRhopagataizca ॥ dikSu budhAGgirasau ravibhaumau sUryasuta: sitazItakarau ca ॥ 2-19 ॥
hk transliteration by Sanscript