Sunan Ibn Majah, Book 1, Hadith 607 (In-Book) ⓘ
It was narrated that Anas bin Malik said: "I saw the Messenger of Allah performing ablution, wearing a Qatari turban. He put his hand beneath the turban and wiped the front part of his head, and he did not take the turban off."
حَدَّثَنَا أَبُو طَاهِرٍ، أَحْمَدُ بْنُ عَمْرِو بْنِ السَّرْحِ حَدَّثَنَا عَبْدُ اللَّهِ بْنُ وَهْبٍ، حَدَّثَنَا مُعَاوِيَةُ بْنُ صَالِحٍ، عَنْ عَبْدِ الْعَزِيزِ بْنِ مُسْلِمٍ، عَنْ أَبِي مَعْقِلٍ، عَنْ أَنَسِ بْنِ مَالِكٍ، قَالَ رَأَيْتُ رَسُولَ اللَّهِ ـ صلى الله عليه وسلم ـ تَوَضَّأَ وَعَلَيْهِ عِمَامَةٌ قِطْرِيَّةٌ فَأَدْخَلَ يَدَهُ مِنْ تَحْتِ الْعِمَامَةِ فَمَسَحَ مُقَدَّمَ رَأْسِهِ وَلَمْ يَنْقُضِ الْعِمَامَةَ .
also referenced under: Hadith 564 (Reference) & Volume 1, Book 1, Hadith 564 (DarusSalam)