I prayed Dhuhr with the Messenger of Allah ﷺ in Madinah as four units, and I prayed Asr with him at Dhul-Hulayfah as two units.
صليت مع رسول الله ﷺ الظهر بالمدينة أربعا، وصليت معه العصر بذي الحليفة ركعتين.
Bukhari narrated it in the chapter on shortening the prayer (1089), and Muslim narrated it in the chapter on the prayer of the traveler (690), both from the hadith of Sufyan, who said, Muhammad bin Munkadir and Ibrahim bin Maysara narrated to us that they heard Anas bin Malik say, then he mentioned it. It has other chains of transmission in the Sahihayn.