(1) باب الْكَرَاهِيَةِ فِي تَأْخِيرِ الْوَصِيَّةِ
It was narrated from Salim bin 'Abdullah, from his father, that the Messenger of Allah said:
"It is not right for a Muslim who has anything concerning which a will should be made, to abide for more than three nights without having a written will with him." (ID)
Reference (ID): Sunan an-Nasa'i 3619 (ID)
In-book reference (ID): Book 30, Hadith 9 (ID)
English translation (ID): Vol. 4, Book 30, Hadith 3649 (ID)