حَدَّثَنَا قُتَيْبَةُ بْنُ سَعِيدٍ، حَدَّثَنَا بِشْرُ بْنُ الْمُفَضَّلِ، عَنْ عَبْدِ الرَّحْمَنِ بْنِ إِسْحَاقَ، هُوَ الْقُرَشِيُّ عَنْ أَبِي عُبَيْدَةَ بْنِ مُحَمَّدِ بْنِ عَمَّارِ بْنِ يَاسِرٍ، قَالَ سَأَلْتُ جَابِرَ بْنَ عَبْدِ اللَّهِ عَنِ الْمَسْحِ، عَلَى الْخُفَّيْنِ فَقَالَ السُّنَّةُ يَا ابْنَ أَخِي ‏.‏ قَالَ وَسَأَلْتُهُ عَنِ الْمَسْحِ، عَلَى الْعِمَامَةِ فَقَالَ أَمِسَّ الشَّعَرَ الْمَاءَ ‏.‏

Abu Ubaidah bin Muttammad bin Ammar bin Yasir said: "I asked Jabir bin Abdullah about wiping over the Khuff. He said, 'O my nephew! It is the Sunnah.'" [He said:] "And I asked him about wiping over the lmamah. He said, '[Wipe1 the hair [with water].'" Translation Not Available

Book Ref: Jamiya Tirmidhi Book 1 Hadith 102
Web Ref:  Jamiya Tirmidhi Vol 1 Book 1 Hadith 102