Sunan Ibn Majah, Volume 4, Book 32, Hadith 3615 (DarusSalam) ⓘ
It was narrated that Anas said: “The sandals of the Prophet had two thongs.”
حَدَّثَنَا أَبُو بَكْرِ بْنُ أَبِي شَيْبَةَ، حَدَّثَنَا يَزِيدُ بْنُ هَارُونَ، عَنْ هَمَّامٍ، عَنْ قَتَادَةَ، عَنْ أَنَسٍ، قَالَ كَانَ لِنَعْلِ النَّبِيِّ ـ صلى الله عليه وسلم ـ قِبَالاَنِ .
also referenced under: Hadith 3615 (Reference) & Book 32, Hadith 3746 (In-Book)