Hadithcore
Sahih al-Bukhari, 4470
sahih

Narrated Ibn Abu Habib:

Abu Al-Khair said, "As-Sanabih, I asked (me), 'When did you migrate?' I (i.e. Abu Al-Khair) said, 'We went out from Yemen as emigrants and arrived at Al-Juhfa, and there came a rider whom I asked about the news. The rider said: We buried the Prophet (ﷺ) five days ago." I asked (As-Sanabihi), 'Did you hear anything about the night of Qadr?' He replied, 'Bilal, the Mu'adh-dhin of the Prophet (ﷺ) informed me that it is on one of the seven nights of the last ten days (of Ramadan).

حَدَّثَنَا أَصْبَغُ، قَالَ أَخْبَرَنِي ابْنُ وَهْبٍ، قَالَ أَخْبَرَنِي عَمْرٌو، عَنِ ابْنِ أَبِي حَبِيبٍ، عَنْ أَبِي الْخَيْرِ، عَنِ الصُّنَابِحِيِّ، أَنَّهُ قَالَ لَهُ مَتَى هَاجَرْتَ قَالَ خَرَجْنَا مِنَ الْيَمَنِ مُهَاجِرِينَ، فَقَدِمْنَا الْجُحْفَةَ، فَأَقْبَلَ رَاكِبٌ فَقُلْتُ لَهُ الْخَبَرَ فَقَالَ دَفَنَّا النَّبِيَّ صلى الله عليه وسلم مُنْذُ خَمْسٍ‏.‏ قُلْتُ هَلْ سَمِعْتَ فِي لَيْلَةِ الْقَدْرِ شَيْئًا قَالَ نَعَمْ أَخْبَرَنِي بِلاَلٌ مُؤَذِّنُ النَّبِيِّ صلى الله عليه وسلم أَنَّهُ فِي السَّبْعِ فِي الْعَشْرِ الأَوَاخِرِ‏.‏

References2 variants
In-Book Reference
Book 64, Hadith 485
USC-MSA web (English) reference
Vol. 5, Book 59, Hadith 746 (deprecated numbering scheme)