Sahih Muslim
The Book Pertaining to the Excellent Qualities of the Holy Prophet (may Peace be upon them) and His Companions (Kitab Al-Fadail)
Book Number: 030 / Hadith Number: 5857
Abu Sa'id Kudari reported Allah's Messenger (may peace be upon him) having, said this: Don't make distinction amongst the Apostles. This hadith has been narrated through another chain of transmitters also.