Musnad Ahmad 30:3513

'Abd al-Samad narrated to us, Hammam narrated to us, Qatadah narrated to us, from 'Abd al-Rahman, the freed slave of Umm Burthan, from Abu Hurairah, that the Messenger of Allah (ﷺ) said: He mentioned the like of it, and he did not mention "the day" for us.