Musnad Abu Ya'la al-Mawsili 150:445

'Abd al-A'la ibn Hammad al-Narsi narrated to us, 'Abd Allah ibn Dawud narrated to us, from Hisham ibn 'Urwah, from his father, from 'Aishah—if Allah wills, this is how 'Abd al-A'la dictated it to us—that the Prophet (peace and blessings of Allah be upon him) said: "Delay the Dhuhr prayer during the intense heat."