Sunan Ibn Majah 762
سنن ابن ماجه#762SahihIt was narrated from Anas that:The Prophet saw some sputum in the prayer direction of the mosque and he became so angry that his face turned red. Then a woman from among the Ansar came and scraped it off, and put some Khaluq on that spot. The Messenger of Allah said: "How good this is
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Al-AlbaniSahih
Muhammad Fouad Abd al-BaqiSahih
Zubair Ali ZaiIsnaad Sahih
In-book reference: 4:28