Musnad Abu Ya'la al-Mawsili 115:51

Hadbata narrated to us, Hammam narrated to us, Qatadah narrated to us, Anas bin Malik narrated to us, that he said one day: "I shall certainly narrate to you a hadith that no one will narrate to you after me; I heard it from the Messenger of Allah, may Allah bless him and grant him peace. I heard the Messenger of Allah, may Allah bless him and grant him peace, saying: 'The Hour will not be established—or he said: Among the signs of the Hour—is that knowledge will be lifted, ignorance will appear, wine will be drunk, adultery will become widespread, men will decrease, and women will increase, until there is one guardian for fifty women.'"