Brihat Parashara Hora Shastra
सूर्यः पापेन संयुक्तो ह्यथवा पापमध्यगः। सूर्यात् सप्तमगः पापस्तदा पितृवधो भवेत्॥ ३६॥
Early loss of father will take place, if Sūrya is with a malefic, or is hemmed between malefics, as there is another malefic in the 7th from Sūrya.
english translation
sUryaH pApena saMyukto hyathavA pApamadhyagaH। sUryAt saptamagaH pApastadA pitRvadho bhavet॥ 36॥
hk transliteration by Sanscript