Musannaf Ibn Abi Shaybah 12156 — Levelling the grave, and reports

A freed slave of Sayyiduna Ibn Abbas (may Allah be pleased with them both) says that Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) said to me: "When you see people who have buried a dead person and made his grave in a way unlike the graves of the Muslims, then level it to be like the graves of the Muslims."