Musannaf Ibn Abi Shaybah 12096 — Marking the grave and writing on it

It is narrated from al-Muttalib bin Abdullah bin Hantab that when Sayyiduna Uthman bin Maz'un (may Allah be pleased with him) died, the Prophet (peace and blessings be upon him) buried him in Jannat al-Baqi', and then said to a man: "Go to that rock and bring a stone, so that I may set it up on his grave as a marker, by which we will recognise it (later)."