Musnad Ahmad 33:667

'Abd al-Samad narrated to us, my father narrated to me, Wasil, the freed slave of Abu 'Uyaynah, narrated to me, Khalid ibn 'Arfatah narrated to me, from Talhah ibn Nafi', from Jabir ibn 'Abd Allah, who said: We were with the Prophet, peace and blessings of Allah be upon him, when the wind of a foul, stinking carcass rose. The Messenger of Allah, peace and blessings of Allah be upon him, said: "Do you know what this wind is? This is the wind of those who backbite the believers."