Sahih Muslim 2385
Ibn Abu Mulaika reported:
I heard `A'isha as saying and she was asked as to whom Allah's Messenger (ﷺ) would have nominated as his successor if he had to nominate one at all. She said: Abu Bakr. It was said to her: Then whom after Abu Bakr? She said: `Umar. It was said to her. Then whom after `Umar? She said: Abu `Ubaida b. al-Jarrah, and then she kept quiet at this.
وَحَدَّثَنِي الْحَسَنُ بْنُ عَلِيٍّ الْحُلْوَانِيُّ، حَدَّثَنَا جَعْفَرُ بْنُ عَوْنٍ، عَنْ أَبِي عُمَيْسٍ، ح
 وَحَدَّثَنَا عَبْدُ بْنُ حُمَيْدٍ، - وَاللَّفْظُ لَهُ - أَخْبَرَنَا جَعْفَرُ بْنُ عَوْنٍ، أَخْبَرَنَا أَبُو عُمَيْسٍ، عَنِ ابْنِ،
 أَبِي مُلَيْكَةَ سَمِعْتُ عَائِشَةَ، وَسُئِلَتْ، مَنْ كَانَ رَسُولُ اللَّهِ صلى الله عليه وسلم مُسْتَخْلِفًا لَوِ
 اسْتَخْلَفَهُ قَالَتْ أَبُو بَكْرٍ ‏.‏ فَقِيلَ لَهَا ثُمَّ مَنْ بَعْدَ أَبِي بَكْرٍ قَالَتْ عُمَرُ ‏.‏ ثُمَّ قِيلَ لَهَا مَنْ بَعْدَ
 عُمَرَ قَالَتْ أَبُو عُبَيْدَةَ بْنُ الْجَرَّاحِ ‏.‏ ثُمَّ انْتَهَتْ إِلَى هَذَا ‏.‏