"Prior to the Battle of Jamal he [Imam Ali] wrote a letter to Ayesha in which he said 'by leaving your home you have opposed the order of Allah (swt) and his Rasul (s)"
Sunni reference: Tadkhirath al Khawwas page 38, Matalib al Sa'ul page 112 and Fusul ul Muhimma page 72
"In Kufa Abu Burdha Azdi asked Hadhrath 'Ali, 'why were people killed at Jamal?'. 'Ali replied 'They killed my Shi'a and my officials without any justification, then they fought me, despite the fact that they gave me bayya, they killed 1000 of my companions".
Sunni reference: Muttalib al Saul page 119
Letter to Aisha from Imam Ali (as) "Tell me Ayesha what role do women have in leading armies and reforming the Ummah? You claim that you want to avenge Uthman's blood, Uthman was a man from Banu Ummaya whilst you are a woman from Banu Taym Ibn Murra"
Sunni reference: Muttalib al Saul page 116
'Ali (as) in a letter written to Ayesha: "You have acted in opposition to Allah (swt) and his Rasul (s) by leaving your home, you have made demands for those things that you have no right. You claim to wish to reform the Ummah, tell me, what role do women have in reforming the Ummah and participating in battles? You claim that you wish to avenge Uthman's murder despite the fact that he is a man from Banu Ummayya and you are a woman from Banu Taym. If we look in to the matter it was only yesterday that you had said 'Kill Nathal May Allah (swt) kill him because he has become a kaafir"
Sunni reference: Seerath al Halabiyya Vol. 3 page 356