Agnipurana 211.13

211.13

mucyate pretalokāttu ṣaṇmāse cāvdikādiṣu /
daśahastena kuṇḍena triṃśatkuṇḍānnivartanaṃ //

is freed from the world of ghosts, as also at six months, the annual rite, and so on. / By a rod of ten cubits, thirty rods make a nivartana;