Musnad Ahmad 459:19

Haywah ibn Shurayh—meaning Ibn Yazid al-Hadrami—and Yazid ibn Abd Rabbih narrated to us, they said: Baqiyyah narrated to us, he said: Buhayr ibn Sa’d narrated to me, from Khalid ibn Ma’dan, from Ibn Abi Bilal, from Irbad ibn Sariyah, that the Messenger of Allah (peace and blessings of Allah be upon him) said: "The martyrs and those who die upon their beds will dispute before our Lord, the Almighty and Majestic, regarding those who die of the plague. The martyrs will say: 'Our brothers were killed just as we were killed.' And those who die upon their beds will say: 'Our brothers died upon their beds just as we died upon our beds.' So our Lord, the Almighty and Majestic, will say: 'Look at their wounds. If their wounds resemble the wounds of the slain, then they are of them and with them.' And behold, their wounds will have resembled their wounds."