Sahih Muslim , Book 20, Hadith 4616 (USC-MSA) ⓘ
The same tradition has been narrated on the authority of Urwat al-Bariqi who said that the Prophet said: Great good is attached to the forelock of the horses until the Day of Judgment.
وَحَدَّثَنَا مُحَمَّدُ بْنُ عَبْدِ اللَّهِ بْنِ نُمَيْرٍ، حَدَّثَنَا أَبِي، حَدَّثَنَا زَكَرِيَّاءُ، عَنْ عَامِرٍ، عَنْ عُرْوَةَ الْبَارِقِيِّ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " الْخَيْلُ مَعْقُودٌ فِي نَوَاصِيهَا الْخَيْرُ إِلَى يَوْمِ الْقِيَامَةِ الأَجْرُ وَالْمَغْنَمُ " .
also referenced under: Book 33, Hadith 145 (In-Book) & Hadith 1873 (Reference)