مُسْنَدُ أَحْمَدَ
Musnad Ahmad 3106
Musnad of 'Abdullah bin al-'Abbas bin 'Abdul-Muttalib from the Prophet
It was narrated that Abu Jamrah said: I heard Ibn 'Abbas (رضي الله عنه) say: The Messenger of Allah(ﷺ) used to pray thirteen rak'ahs at night.
Musnad Ahmad 3130Its isnad is saheeh, al-Bukhari (1138) and Muslim (764)]