مُسْنَدُ أَحْمَدَ
Musnad Ahmad 2962
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 Prophet (ﷺ) used to pray thirteen rak'ahs at night.
Musnad Ahmad 2985Its isnad is saheeh, al-Bukhari (1138) and Muslim (764)]