Sunan Abi Dawud Book 5, Hadith 20
The Prophet (ﷺ) said: If anyone keeps on praying regularly four rak'ahs before and four after the noon prayer, he will not enter the Hell-fire.
Abu Dawud said: Al-'Ala' bin Al-Harith and Sulaiman bin Musa reported it from Makhul with his chain, similarly.
'Abd Rabbihi and Yahya b. Sa'id also narrated this tradition from the Prophet (ﷺ) omitting the name of the Companion (mursal). Their grandfather Zaid prayed along with the Prophet (ﷺ).
The Prophet (ﷺ) said: The gates of heaven are opened for four rak'ahs containing no taslim (salutation) before the noon prayer.
Abu Dawud said: Yahya b. Sa'id al-Qattan said: If I were to narrate any tradition from 'Ubaidah, I would narrate this tradition.
Abu Dawud said: 'Ubaidah is weak.
Abu Dawud said: The name of the narrator Ibn Minjab is Sahm.