Mu'awiya is baat par razi tha ke uske baad khilafat Imam Hasan A.S ko milegi.
Janab hamari kitabe chodiye zara apni par ghor kijiye.
Fathul Bari fin Sharh Bukhari Volume 3 page 65 Kitab al Fitan
Mirqat Sharh Mishqat Volume 11 page 38 Bab Manaqib Ahl'ul Bayt
Al Bidayah Wal Nihayah (Urdu), Vol 8 Page 871 'The events of 56 Hijri'
Hayaath al Haywaan Volume 1 page 53 Dhikr Khilafa
Tareekh Khamees Volume 2 page 29 Dhikr Hasan
Al Imama wa al Siyasa page 18 Sulh Hasan
Al Istiab Volume 1 page 370 Dhikr Hasan