Hadith 3:112
Al-Mustaurid b. Shaddad said that he saw God’s messenger rubbing his toes with his little finger when he performed ablution. Tirmidhi, Abu Dawud and Ibn Majah transmitted it.
وَعَن الْمُسْتَوْرد بن شَدَّاد قَالَ: رَأَيْتُ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ إِذَا تَوَضَّأَ يُدَلِّكُ أَصَابِعَ رِجْلَيْهِ بِخِنْصَرِهِ. رَوَاهُ التِّرْمِذِيّ وَأَبُو دَاوُد وَابْن مَاجَه
Original Reference: Mishkat al-Masabih 407