Musannaf Ibn Abi Shayba 3:4947

Jarir narrated to us, from Mansur, from Hilal ibn Yasaf, from Wahb ibn al-Ajda’, from Ali, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "There is no prayer after the afternoon (Asr) prayer, unless the sun is white and pure."