Complex sentence: Other historians such as Dinawari, Ibn Abd al-Barr and Ibn al-Athir record different accounts of the conditions, and the timing of the black sheet sent by Mu'awiyah to Hasan was confusing in Tabari's account.
Split into simpler sentences: Other historians such as Dinawari, Ibn Abd al-Barr and Ibn al-Athir record different accounts of the conditions. And the timing of the black sheet sent by Mu'awiyah to Hasan was confusing in Tabari's account.