Sahih Muslim
The Book of Mosques and Places of Prayer
وَحَدَّثَنَا مُحَمَّدُ بْنُ الْمُثَنَّى، حَدَّثَنَا عَبْدُ الأَعْلَى، حَدَّثَنَا سَعِيدٌ، عَنْ قَتَادَةَ، عَنْ أَنَسِ بْنِ مَالِكٍ، قَالَ قَالَ نَبِيُّ اللَّهِ صلى الله عليه وسلم
مَنْ نَسِيَ صَلاَةً أَوْ نَامَ عَنْهَا فَكَفَّارَتُهَا أَنْ يُصَلِّيَهَا إِذَا ذَكَرَهَا
Qatada narrated on the authority of Anas b. Malik that the Messenger of Allah (ﷺ) said: He who forgets the prayer, or he slept (and it was omitted), its expiation is (only) that he should observe it when he remembers it.
وَحَدَّثَنَا نَصْرُ بْنُ عَلِيٍّ الْجَهْضَمِيُّ، حَدَّثَنِي أَبِي، حَدَّثَنَا الْمُثَنَّى، عَنْ قَتَادَةَ، عَنْ أَنَسِ بْنِ مَالِكٍ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم
إِذَا رَقَدَ أَحَدُكُمْ عَنِ الصَّلاَةِ أَوْ غَفَلَ عَنْهَا فَلْيُصَلِّهَا إِذَا ذَكَرَهَا فَإِنَّ اللَّهَ يَقُولُ أَقِمِ الصَّلاَةَ لِذِكْرِي
Qatada reported it on the authority of Anas b. Malik that the Messenger of Allah (ﷺ) said: When any one of you omits the prayer due to sleep or he forgets it, he should observe it when he remembers it, for Allah has said:" Observe prayer for remembrance of Me."