[Al-Bukhari and Muslim]
Riyad-us-Saliheen – Hadith No: 1113
`Aishah (May Allah be pleased with her) reported: The Prophet (PBUH) never omitted four Rak`ah supererogatory prayer before Zuhr prayers.
Riyad-us-Saliheen – Hadith No: 1114
Some Ahadith state that he (PBUH) used to perform two Rak`ah before and two after Zuhr prayer. The present Hadith says that he used to perform four Rak`ah before Zuhr prayer. Both narrations are correct and can be followed according to conditions and circumstances.
Please Share this Hadith with your relatives & friends and may Allah SWT reward you.