Language:
كتاب الغسل
5
Bathing (Ghusl)
(7)
Chapter: To rinse the mouth and to clean the nose by putting water in it and then blowing it out while taking the bath of Janaba
(7)
باب الْمَضْمَضَةِ وَالاِسْتِنْشَاقِ فِي الْجَنَابَةِ
Sahih al-Bukhari 259

Narrated Maimuna:

I placed water for the bath of the Prophet (ﷺ) and he poured water with his right hand on his left and washed them. Then he washed his private parts and rubbed his hands on the ground, washed them with water, rinsed his mouth and washed his nose by putting water in it and blowing it out, washed his face and poured water on his head. He withdrew from that place and washed his feet. A piece of cloth (towel) was given to him but he did not use it.

حَدَّثَنَا عُمَرُ بْنُ حَفْصِ بْنِ غِيَاثٍ، قَالَ حَدَّثَنَا أَبِي، حَدَّثَنَا الأَعْمَشُ، قَالَ حَدَّثَنِي سَالِمٌ، عَنْ كُرَيْبٍ، عَنِ ابْنِ عَبَّاسٍ، قَالَ حَدَّثَتْنَا مَيْمُونَةُ، قَالَتْ صَبَبْتُ لِلنَّبِيِّ صلى الله عليه وسلم غُسْلاً، فَأَفْرَغَ بِيَمِينِهِ عَلَى يَسَارِهِ فَغَسَلَهُمَا، ثُمَّ غَسَلَ فَرْجَهُ، ثُمَّ قَالَ بِيَدِهِ الأَرْضَ فَمَسَحَهَا بِالتُّرَابِ، ثُمَّ غَسَلَهَا، ثُمَّ تَمَضْمَضَ وَاسْتَنْشَقَ، ثُمَّ غَسَلَ وَجْهَهُ، وَأَفَاضَ عَلَى رَأْسِهِ، ثُمَّ تَنَحَّى فَغَسَلَ قَدَمَيْهِ، ثُمَّ أُتِيَ بِمِنْدِيلٍ، فَلَمْ يَنْفُضْ بِهَا‏.‏
Reference : Sahih al-Bukhari 259
In-book reference : Book 5, Hadith 12
USC-MSA web (English) reference : Vol. 1, Book 5, Hadith 259
  (deprecated numbering scheme)