Zuhayr narrates from Abu Ishaq (may Allah have mercy on him) that he attended the funeral of al-Harith al-A'war. Abdullah bin Yazid (may Allah be pleased with him) refused to let them spread a cloth over him, and he said: He is a man. Abu Ishaq (may Allah have mercy on him) says: Abdullah bin Yazid (may Allah be pleased with him) had seen the Messenger of Allah (peace and blessings be upon him).
This chain is sahih (authentic), even though it is mawquf (stopping at the Companion); a group narrated it from Abu Ishaq.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الجنائز / 7050