Reference: Siyar A’laam an-Nubalaa – Volume 5, Page 258
al-Hifth – Ahammiyyatuhu, ‘Ajaa.ibuhu, Tareeqatuhu, Asbaabuhu – Page 27
‘Aasim ibn an-Najwad (died 128 AH) said:
I was ill for 2 years, and when I got better, I read the Qur.aan [from memory] and I did not make a single mistake.