مُسْنَدُ أَحْمَدَ
Musnad Ahmad 3780
Musnad of Abdullah bin Mas'ood
It was narrated that 'Abdullah (رضي الله عنه) said: I heard a man reciting Ha-Meem (i.e., al-Ahqaf); he recited it in one mode of recitation and another man recited it in another mode of recitation that his companion did not use, and I recited it in yet another mode of recitation that my two companions had not used. We came to the Prophet (ﷺ) and told him, and he said: "Do not differ; those who came before you were destroyed because they differed." Then he said: "See which one among you has the most knowledge of recitation, and follow his recitation."
Musnad Ahmad 3803Saheeh, its isnad is hasan, al-Bukhari (2410)]