Yahya related to me from Malik from Da'ud ibn al-Husayn from al-Araj from Abu Hurayra that the Messenger of Allah, may Allah bless himand grant him peace, joined dhuhr and asr on his journey to Tabuk. (IT)
USC-MSA web (English) reference: Book 9, Hadith 1 (IT)
Arabic reference (IT): Book 9, Hadith 329 (IT)