The Book of Purification
1/51. Chapter:
What Is Leftover From A Dog
Sunan an-Nasai
أَخْبَرَنَا قُتَيْبَةُ، عَنْ مَالِكٍ، عَنْ أَبِي الزِّنَادِ، عَنِ الأَعْرَجِ، عَنْ أَبِي هُرَيْرَةَ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ " إِذَا شَرِبَ الْكَلْبُ فِي إِنَاءِ أَحَدِكُمْ فَلْيَغْسِلْهُ سَبْعَ مَرَّاتٍ " .
It was narrated from Abu Hurairah that the Messenger of Allah (ﷺ) said: "If a dog drinks from the vessel of one of you, let him wash it seven times."
Reference : Sunan an-Nasa'i 63In-book reference : Book 1, Hadith 63English translation : Vol. 1, Book 1, Hadith 63