'Abdul-Muhaimin bin 'Abbas bin Sahl bin Sa'd As-Sa'di narraed from his father, from his grandfather, that:
The Messenger of Allah said: "Rinse your mouths after drinking milk, for it has some greasiness in it." (AR)
English reference (AR): Vol. 1, Book 1, Hadith 500 (AR)
Arabic reference (AR): Book 1, Hadith 539 (AR)