The Book Pertaining to the Excellent Qualities of the Holy Prophet (may Peace be upon them) and His Companions (Kitab Al-Fada'il)
Muslim :: Book 30 : Hadith 5743
Anas reported that Allah's Messenger (may peace be upon him) had in one of his journeys his black slave who was called Anjasha along with him. He goaded by singing the songs of camel-driver. Thereupon Allah's Messenger (may peace be upon him) said: Anjasha, drive slowly as you are driving (the mounts who are carrying) glass vessels