ENOfficial
Al-Hasan said on Samura’s authority that God’s Messenger forbade that a thong of a sandal should be cut off between two toes. Abu Dawud transmitted it.
Source: sunnah.com
Other translations
Arabic
وَعَن الحسنِ عَنْ سَمُرَةَ أَنَّ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ نَهَى أَنْ يُقَدَّ السَّيْرُ بَيْنَ أُصبعَينِ. رَوَاهُ أَبُو دَاوُد
sunnah.com