Ata narrates from Sayyiduna Ibn Abbas (may Allah be pleased with them both) that the Messenger of Allah (peace and blessings be upon him) said: "Cover the faces of your dead, and do not imitate the Jews."
If this is authentic, it supports the narration of Ibrahim bin Abi Hurrah regarding the command to cover the face. However, Ahmad bin Hanbal rejected it and said: Hafs erred in it by making it marfu' (attributed to the Prophet); it is from Ata, mursal. Al-Thawri and others likewise narrated it from Ibn Jurayj as mursal, and the narration from Ali bin Asim from Ibn Jurayj in the manner of Hafs is an error (wahm). And Allah knows best.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الجنائز / 6652