Ramayana
स राक्षसस्तत्र सहानुजस्तदा तपश्चकारातुलमुग्रविक्रमः । अतोषयच्चापि पितामहं विभुं ददौ स तुष्टश्च वराञ्जयावहान् ॥ 7-9-48 ॥
That rakshasa of fierce prowess, together with his younger brothers, then performed there austerity beyond compare, and he gratified the mighty Grandfather Brahma; and Brahma, well pleased, granted them boons that bring victory.
english translation