It is narrated from Sayyiduna al-Nu'man bin Bashir (may Allah be pleased with them both) that he was present with Sayyiduna Zayd bin Kharijah (may Allah be pleased with him) when he spoke after he had died and been covered with a cloth. Al-Nu'man (may Allah be pleased with him) said that the first thing he said was: "Muhammad (peace and blessings be upon him) is the Messenger of Allah; I bear true witness. Abu Bakr (may Allah be pleased with him), who is weak in the eyes of people, is strong in the matter of Allah; I bear true witness. Umar bin al-Khattab (may Allah be pleased with him) is strong and trustworthy; I bear true witness."
Imam al-Tabarani (may Allah have mercy on him) said: "No one narrated this hadith from al-Zuhri (may Allah have mercy on him) except Bukayr, and no one from Bukayr except Amr bin al-Harith; Ibn Wahb is alone in it."
Hadith Referenceالمعجم الأوسط / باب الميم / 7687
Hadith Takhrij«أخرجه الطبراني فى «الكبير» برقم: 5144، 5145»