Manava Dharmashastra 11.74

11.74

yajeta vāśvamedhena svarjitā gosavena vā
abhijidviśvajidbhyāṃ vā trivṛtāgniṣṭutāpi vā //

Or let him, of his own free will, become (in a battle) the target of archers who know (his purpose); or he may thrice throw himself headlong into a blazing fire;