Sahih Bukhari Volume 004, Book 052, Hadith Number 049.
Hadith Section/Book: Sahih Bukhari Sahih Bukhari Book 52. Fighting for the Cause of Allah (Jihaad)
Narated By Samura : The Prophet said, "Last night two men came to me (in a dream) and made me ascend a tree and then admitted me into a better and superior house, better of which I have never seen. One of them said, 'This house is the house of martyrs."