مُسْنَدُ أَحْمَدَ
Musnad Ahmad 3578
Musnad of Abdullah bin Mas'ood
It was narrated that 'Abdullah (رضي الله عنه) said: The Messenger of Allah (ﷺ) said: “Perhaps you will see people who offer the prayer at the wrong time. If you see them, offer the prayer in your houses at the time you know, then pray with them and make it nafl."
Musnad Ahmad 3601lts isnad is hasan]