Sunan an-Nasa'i, Volume 5, Book 45, Hadith 4850 (DarusSalam) ⓘ
It was narrated from Sa'eed bin al-Musayyab that: when the letter was found that was with the family of 'Amr bin Hazm, which they said the Messenger of Allah had written to them, they found in it, with regard to fingers, that the Diyahwas ten (Camels) for each.
أَخْبَرَنَا الْحُسَيْنُ بْنُ مَنْصُورٍ، قَالَ حَدَّثَنَا عَبْدُ اللَّهِ بْنُ نُمَيْرٍ، قَالَ حَدَّثَنَا يَحْيَى بْنُ سَعِيدٍ، عَنْ سَعِيدِ بْنِ الْمُسَيَّبِ، أَنَّهُ لَمَّا وُجِدَ الْكِتَابُ الَّذِي عِنْدَ آلِ عَمْرِو بْنِ حَزْمٍ الَّذِي ذَكَرُوا أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم كَتَبَ لَهُمْ وَجَدُوا فِيهِ " وَفِيمَا هُنَالِكَ مِنَ الأَصَابِعِ عَشْرًا عَشْرًا " .
also referenced under: Hadith 4846 (Reference) & Book 45, Hadith 141 (In-Book)