Musnad Ahmad 30:3316

Waki’ narrated to us, al-A’mash narrated to us, from Abu Salih, from Abu Hurairah, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said—then he mentioned a hadith, and then said: "Would any one of you like, when he returns to his family, to find three large, fat pregnant she-camels? Three verses that one of you recites in his prayer are better for him than three large, fat pregnant she-camels."