Brihat Parashara Hora Shastra
उभयस्थास्तु सूर्याद्या पश्यन्युभयसंस्थितान्। निकटस्थं विना खेटाः पश्यन्तीत्ययमागमः॥ ५॥
The one in a Common Rāśi gives a Drishti to the remaining 3 Common Rāśis. Simultaneously a Grah in the Rāśi, that receives a Drishti, is also subjected to the Drishti concerned.
english translation
ubhayasthAstu sUryAdyA pazyanyubhayasaMsthitAn। nikaTasthaM vinA kheTAH pazyantItyayamAgamaH॥ 5॥
hk transliteration by Sanscript