Yahya related to me from Malik from Da'ud ibn al-Husayn that IbnYarbu al-Makhzumi said, "I heard Zayd ibn Thabit say, 'The middleprayer is the prayer of dhuhr.' " (PT)
App reference (PT): Book 8, Hadith 28 (PT)
USC-MSA web (English) reference: Book 8, Hadith 28 (PT)
Arabic reference (PT): Book 8, Hadith 317 (PT)