The Book of Purification
1/193. Chapter:
Spittle That Gets On Clothes
Sunan an-Nasai
أَخْبَرَنَا عَلِيُّ بْنُ حُجْرٍ، قَالَ حَدَّثَنَا إِسْمَاعِيلُ، عَنْ حُمَيْدٍ، عَنْ أَنَسٍ، أَنَّ النَّبِيَّ صلى الله عليه وسلم أَخَذَ طَرَفَ رِدَائِهِ فَبَصَقَ فِيهِ فَرَدَّ بَعْضَهُ عَلَى بَعْضٍ .
It was narrated from Anas that the Prophet (ﷺ took the hem of his garment and spat on it, rubbed it together briefly and let it drop.
Reference : Sunan an-Nasa'i 308In-book reference : Book 1, Hadith 309English translation : Vol. 1, Book 1, Hadith 309