'Ali Radiyallahu 'Anhu used to perform four rak'ahs before zuhr and used to say:
"Rasulullah Sallallahu 'Alayhi Wasallam also performed these four rak'ahs after zawaal, and recited long verses therein". (FR)
English reference (FR): Book 40, Hadith 279 (FR)
Arabic reference (FR): Book 41, Hadith 296 (FR)