Brihat Parashara Hora Shastra
द्विनाथक्षेत्रयोरत्र क्रियते निर्णयोऽधुना । द्वावेवाधिपती विप्र युक्तौ स्वर्क्षे स्थितौ यदि ॥ १५८॥
Now I will tell you about the working out of the Dasha years of Vrischik and Kumbh. If both the Lords of the two Rāśis, Vrischik and Kumbh, are placed in their own Rāśis.
english translation
dvinAthakSetrayoratra kriyate nirNayo'dhunA । dvAvevAdhipatI vipra yuktau svarkSe sthitau yadi ॥ 158॥
hk transliteration by Sanscript