Agniveshyagrihyasutra 3.11.4.40

3.11.4.40

evameva śastraviparajjujaladarvīkaramārutatarupāṣāṇocchāsanādiṣvātmanihatasya vā gobrāhmaṇavidhavāpatiteṣvāpatitasya vā śarīrasaṃskārān varjayet \

In the same manner, one should omit bodily rites for one who killed himself by weapon, poison, rope, water, a hooded serpent, wind, a tree, a stone, suffocation, and the like, or for one who has fallen among cows, Brahmins, widows, or outcasts.