Qataadah radiallahu anhu reports that:
"I asked Anas to describe the shoe of Rasulullah Sayyidina Rasulullah sallallahu alaihe wasallam". He replied: "Each shoe had two straps" (IT)
English reference (IT): Book 10, Hadith 71 (IT)
Arabic reference (IT): Book 11, Hadith 75 (IT)