Jami` at-Tirmidhi, Volume 2, Book 8, Hadith 1038 (DarusSalam) ⓘ
Sa'eedbin Musayyab narrated: "Umm Sa'd died while the Prophet was absent. So when he arrived he performed Salat over her, and a month had already passed."
حَدَّثَنَا مُحَمَّدُ بْنُ بَشَّارٍ، حَدَّثَنَا يَحْيَى بْنُ سَعِيدٍ، عَنْ سَعِيدِ بْنِ أَبِي عَرُوبَةَ، عَنْ قَتَادَةَ، عَنْ سَعِيدِ بْنِ الْمُسَيَّبِ، أَنَّ أُمَّ سَعْدٍ، مَاتَتْ وَالنَّبِيُّ صلى الله عليه وسلم غَائِبٌ فَلَمَّا قَدِمَ صَلَّى عَلَيْهَا وَقَدْ مَضَى لِذَلِكَ شَهْرٌ .
also referenced under: Hadith 1038 (Reference) & Book 10, Hadith 74 (In-Book)