Mishkat al-Masabih #1542
Funerals
The Arabic includes the chain of narration (sanad) and the collector's commentary; the English translation shows the Prophet's words only.
وَعَن عَائِشَةَ قَالَتْ: إِنَّ أَبَا بَكْرٍ قَبَّلَ النَّبِيَّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ وَهُوَ مَيِّتٌ. رَوَاهُ التِّرْمِذِيّ وَابْن مَاجَه
She said that Abu Bakr kissed the Prophet when he was dead.
Tirmidhi and Ibn Majah transmitted it.
About Mishkat al-Masabih
This hadith is #1542 from Mishkat al-Masabih, in the Book of Funerals.