مُسْنَدُ أَحْمَدَ
Musnad Ahmad 2561
Musnad of 'Abdullah bin al-'Abbas bin 'Abdul-Muttalib from the Prophet
It was narrated from Ibn 'Abbas (رضي الله عنه) that They started asking him about prayer whilst travelling. Ibn 'Abbas (رضي الله عنه) said: When the Prophet (ﷺ) departed from his family, he would pray no more than two rak'ahs until he returned.
Musnad Ahmad 2575Its isnad is saheeh]