Sunan Ibn Majah, Book 22, Hadith 2806 (In-Book) ⓘ
It was narrated from Ibn 'Umar that the Prophet said: “The Muslim man has no right to spend two nights, if he has something for which will should be made, without having a written will with him.”
حَدَّثَنَا مُحَمَّدُ بْنُ مَعْمَرٍ، حَدَّثَنَا رَوْحُ بْنُ عَوْفٍ، عَنْ نَافِعٍ، عَنِ ابْنِ عُمَرَ، عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ " مَا حَقُّ امْرِئٍ مُسْلِمٍ يَبِيتُ لَيْلَتَيْنِ وَلَهُ شَىْءٌ يُوصِي بِهِ إِلاَّ وَوَصِيَّتُهُ مَكْتُوبَةٌ عِنْدَهُ " .
also referenced under: Hadith 2702 (Reference) & Volume 3, Book 22, Hadith 2702 (DarusSalam)