Ash-Shama'il Al-Muhammadiyah, Book 19, Hadith 119 (English) ⓘ
Hazrat Anas bin Malik radiyallahu anhu says, "Rasoollullah sallallahu alaihe wasallam often wore a cloth on his auspicious head. This cloth, because of its greasiness, looked as if had been oiled.
حَدَّثَنَا يُوسُفُ بْنُ عِيسَى، قَالَ: حَدَّثَنَا وَكِيعٌ، قَالَ: حَدَّثَنَا الرَّبِيعُ بْنُ صَبِيحٍ، عَنْ يَزِيدَ بْنِ أَبَانَ، عَنْ أَنَسِ بْنِ مَالِكٍ، قَالَ: كَانَ رَسُولُ اللهِ صلى الله عليه وسلم يُكْثِرُ الْقِنَاعَ، كَأَنَّ ثَوْبَهُ ثَوْبُ زَيَّاتٍ.
also referenced under: Book 20, Hadith 126 (In-Book)