Valmiki Ramayana Bala Kanda Sarga 3 Shloka 28
Original Shlokaसिंहिकायाश्च निधनं लङ्कामलयदर्शनम् । रात्रौ लङ्काप्रवेशं च एकस्याथ विचिन्तनम् ।।1.3.28।।
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सिंहिकाया: Simhika's, निधनम् death, लङ्कामलयदर्शनम् viewing a mountain in Lanka, रात्रौ by night, लङ्काप्रवेशं च entry into Lanka, अथ thereafter, एकस्य lonely Hanuman's, विचिन्तनम् thinking.
(He described) the slaughter of (the female demon) Simhika, the viewing of in Lanka from a mountain, the entry into Lanka by night and thereafter, Hanuman's lonely thinking.