Brihat Parashara Hora Shastra
ज्ञेज्यदृष्टियुतं तच्च स्वस्वस्वामिबलान्वितम् । इति भावबलं स्पष्टं सामान्यं च पुरोदितम् ॥ २९॥
If the Bhava receives a malefic Drishti, one fourth should be reduced. If Guru, or Budh give a Drishti to a Bhava, add that Grah‟s Drik Bal also. And then superadd the strength, acquired by the Lord of that Bhava. This will be the net Bhava Bal.
english translation
jJejyadRSTiyutaM tacca svasvasvAmibalAnvitam । iti bhAvabalaM spaSTaM sAmAnyaM ca puroditam ॥ 29॥
hk transliteration by Sanscript