Jami` at-Tirmidhi Book 10, Hadith 75
the Prophet said: "Indeed your brother An-Najashi has died. So stand to perform Salat for him." He (Imran) said: "We stood and lined up just as the deceased is lined up for, and we prayed for him just as the deceased is prayed for."
"Umm Sa'd died while the Prophet was absent. So when he arrived he performed Salat over her, and a month had already passed."
The Messenger of Allah said: "Whoever performs the funeral prayer then he will get a reward equal to a Qirat. Whoever follows it until it is buried then he will get a reward equal to two Qirat, one of them, or the least of them, is similar to Uhud (mountain)." This was mentioned to Ibn Umar, so he sent a message to Aishah to ask her about that, and she said: "Abu Hurairah has told the truth." So Ibn Umar said: "We have missed many Qirat."