It is narrated from Sayyiduna Abu Hurayrah (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) passed by a grave and he (peace and blessings be upon him) asked: "Whose grave is this?" The people replied: "So-and-so." So he (peace and blessings be upon him) said: "Two rak'ahs (of prayer) are dearer to this man than what remains of your world."
No one narrated this hadith from Abu Malik (may Allah have mercy on him) except Hafs bin Ghiyath (may Allah have mercy on him), and Hafs bin Abdullah (may Allah have mercy on him) is alone in narrating it.