سنن النسائي

It was narrated that Jabir said: "A man asked the Messenger of Allah (ﷺ) about the times of prayer. He said: 'Pray with me.' So he prayed Zuhr when the sun had passsed its zenith, 'Asr when the shadow of a thing was equal to its height, Maghrib when the sun had set and 'Isha' when the twilight had disappeared." He said: "Then he prayed Zuhr when the shadow of a man was equal in length to his height, 'Asr when the length of a man's shadow was twice his height, and Maghrib just before the twilight disappeared." (One of the narrators) 'Abdullah bin Al-Harith said: "then he said: 'With regard to 'Isha' I think it is up to one-third of the night.'" [1] [1] The speaker there is Thawr, who narrated it from 'Ata' from Jabir.