Sunan an-Nasa'i, Hadith 5041 ⓘ
Al-Mu'tamir narrated that his father said: "I heard Talq mentioning ten things that have to do with the Fitrah: Using the Siwak, trimming the mustache, clipping the nails, washing the joints, shaving the pubes, rinsing the nose, and I am not sure about rinsing the mouth."
أَخْبَرَنَا مُحَمَّدُ بْنُ عَبْدِ الأَعْلَى، قَالَ حَدَّثَنَا الْمُعْتَمِرُ، عَنْ أَبِيهِ، قَالَ سَمِعْتُ طَلْقًا، يَذْكُرُ عَشْرَةً مِنَ الْفِطْرَةِ السِّوَاكَ وَقَصَّ الشَّارِبِ وَتَقْلِيمَ الأَظْفَارِ وَغَسْلَ الْبَرَاجِمِ وَحَلْقَ الْعَانَةِ وَالاِسْتِنْشَاقَ . وَأَنَا شَكَكْتُ فِي الْمَضْمَضَةِ .
also referenced under: Book 48, Hadith 2 (In-Book) & Volume 6, Book 48, Hadith 5044 (DarusSalam)