It was narrated from 'Abdul Jabbar bin Wa'il that his father said:
"A bucket was brought to the Prophet; he rinsed his mouth and spat into it, and it was like musk or better than musk, and he rinsed his nostrils outside the bucket." (IT)
English reference (IT): Vol. 1, Book 1, Hadith 659 (IT)
Arabic reference (IT): Book 1, Hadith 704 (IT)