Valmiki Ramayana Kishkindha Kanda Sarga 44 Shloka 8
Original Shlokaततः कार्यसमासङ्गमवगम्य हनूमति। विदित्वा हनुमन्तं च चिन्तयामास राघवः।।4.44.8।।
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ततः then, राघवः Rama, हनूमति in Hanuman, कार्यसमासङ्गम् responsibility of achieving the goal, अवगम्य having understood, हनुमन्तं च Hanuman also, विदित्वा knowing, चिन्तयामास reflected.
Having understood that Hanuman was capable of accomplishing the goal, Rama started reflecting as follows: