Muwatta Imam Malik Book of The Qur'an, Hadith 11
Yahya related to me from Malik that he had heard that it took Abdullah ibn Umar eight years to learn Surat al-Baqara. (Sura 2)
وَحَدَّثَنِي عَنْ مَالِكٍ، أَنَّهُ بَلَغَهُ أَنَّ عَبْدَ اللَّهِ بْنَ عُمَرَ، مَكَثَ عَلَى سُورَةِ الْبَقَرَةِ ثَمَانِيَ سِنِينَ يَتَعَلَّمُهَا .