Sahih al-Bukhari, Book 66, Hadith 10 (In-Book) ⓘ

Zaid bin Thabit added, "A verse from Surat Ahzab was missed by me when we copied the Qur'an and I used to hear Allah's Messenger reciting it. So we searched for it and found it with Khuza`ima bin Thabit Al-Ansari. (That Verse was): 'Among the Believers are men who have been true in their covenant with Allah.' (33.23)

قَالَ ابْنُ شِهَابٍ وَأَخْبَرَنِي خَارِجَةُ بْنُ زَيْدِ بْنِ ثَابِتٍ، سَمِعَ زَيْدَ بْنَ ثَابِتٍ، قَالَ فَقَدْتُ آيَةً مِنَ الأَحْزَابِ حِينَ نَسَخْنَا الْمُصْحَفَ قَدْ كُنْتُ أَسْمَعُ رَسُولَ اللَّهِ صلى الله عليه وسلم يَقْرَأُ بِهَا فَالْتَمَسْنَاهَا فَوَجَدْنَاهَا مَعَ خُزَيْمَةَ بْنِ ثَابِتٍ الأَنْصَارِيِّ ‏{‏مِنَ الْمُؤْمِنِينَ رِجَالٌ صَدَقُوا مَا عَاهَدُوا اللَّهَ عَلَيْهِ‏}‏ فَأَلْحَقْنَاهَا فِي سُورَتِهَا فِي الْمُصْحَفِ‏.‏