Valmiki Ramayana Yuddha Kanda Sarga 112 Shloka 19
Original Shlokaइयंहिपूर्वैस्सन्दिष्टागतिःक्षत्रियसम्मता । क्षत्रियोनिहतंसङ्ख्ये न शोच्यइतिनिश्चयः ।।6.112.19।।
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इयम् this, पूर्वैः in the past, सन्दिष्टा in battle, क्षत्रियसम्मता acceptable for ancient kings, गतिः course, सङ्ख्ये action, निहतः killed, क्षत्रियः king, न शोच्यः not mourned, इति this, निश्चयः is true
"This course has been practised in the past by ancient kings for those killed in war. Warrior killed in war is not to be mourned', is true."