Phaladeepika
सूर्यादितोऽत्रांशफलं प्रदिष्टं ज्ञेयं नवांशस्य फलं तदेव । राशीक्षणे यत्फलमुक्तमिन्दो- स्तद्द्वादशांशस्य फलं हि वाच्यम् ॥ १६॥
What has been declared here (in Slokas 12-15) as Amsaphala due to the Moon being posited in the Amsas of the Sun and other planets should be understood to be the effects derived from the Navamsa division The effects that have been declared as resulting from the Moon in the several signs being aspected by the various planets should be stated as applying in the case of the Dwadasamsas also.
english translation
sUryAdito'trAMzaphalaM pradiSTaM jJeyaM navAMzasya phalaM tadeva । rAzIkSaNe yatphalamuktamindo- staddvAdazAMzasya phalaM hi vAcyam ॥ 16॥
hk transliteration by Sanscript