Quran 2:180 — The Heifer (Al-Baqarah)

It is decreed that when death approaches, you shall write a will for the benefit of the parents and relatives, equitably. This is a duty upon the righteous.

[2:179] Equivalence is a life saving law for you, O you who possess intelligence, that you may be righteous.

[2:181] If anyone alters a will he had heard, the sin of altering befalls those responsible for such altering. GOD is Hearer, Knower.