Sayyiduna Amr bin al-As (may Allah be pleased with him) and Sayyiduna Uqbah bin Amir al-Juhani (may Allah be pleased with him) narrate this saying of the Prophet (peace and blessings be upon him): "Indeed, Allah Almighty has granted you an additional prayer, which is better for you than red camels, and it is the witr. It is to be performed in the time between the Isha prayer and true dawn."
Imam al-Tabarani recorded this narration in al-Mu'jam al-Kabir and al-Mu'jam al-Awsat; its chain contains a narrator, Suwayd bin Abd al-Aziz, who is matruk (abandoned).