مُسْنَدُ أَحْمَدَ
Musnad Ahmad 2511
Musnad of 'Abdullah bin al-'Abbas bin 'Abdul-Muttalib from the Prophet
It was narrated that Ibn ‘Abbas (رضي الله عنه) said: The Prophet (ﷺ) stayed in Makkah for fifteen years, seven years during which he saw light and heard a voice, and eight years during which Revelation came to him, and he stayed in Madinah for ten years.
Musnad Ahmad 2523Its isnad is saheeh, Muslim (2353)]