Sahih Bukhari
Virtues of the Quran
Volume: 006 / Book Number: 061 / Hadith Number: 526
Narrated Anas bin Malik:
When the Prophet died, none had collected the Qur'an but four persons;: Abu Ad-Darda'. Mu'adh bin Jabal, Zaid bin Thabit and Abu Zaid. We were the inheritor (of Abu Zaid) as he had no offspring .