Bismillah.

Salam alaikum.

Imam Beyhaki said in Itiqad wal Hadiy ila sabili Rashad (p 494):

The thing that was narrated regarding Ali didn’t pledge allegiance to Abu Bakr 6 months, is not from words of Aisha. That is words of az-Zuhri, which some narrators inserted to hadith of Fatima from Aisha (may Allah be pleased with them). Muamar ibn Rashid memorized it, and narrated it in clear form, and he marked words of az-Zuhri separate from hadith itself.

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