Sunan an-Nasa'i, Hadith 4752 ⓘ
It was narrated from Anas that: the Messenger of Allah ruled that Qisas should be given for a tooth. The Messenger of Allah said: "The Messenger of Allah said: "What Allah has decreed is retaliation."
أَخْبَرَنَا إِسْحَاقُ بْنُ إِبْرَاهِيمَ، قَالَ أَنْبَأَنَا أَبُو خَالِدٍ، سُلَيْمَانُ بْنُ حَيَّانَ قَالَ حَدَّثَنَا حُمَيْدٌ، عَنْ أَنَسٍ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَضَى بِالْقِصَاصِ فِي السِّنِّ وَقَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " كِتَابُ اللَّهِ الْقِصَاصُ " .
also referenced under: Book 45, Hadith 47 (In-Book) & Volume 5, Book 45, Hadith 4756 (DarusSalam)