Abu Qataadah Radiyallahu 'Anhu reports that Rasulullah Sallallahu 'Alayhi Wasallam said:
"Whomsoever sees me, that is, in a dream, has seen that which is a fact". (AR)
App reference (AR): Book 56, Hadith 7 (AR)
English reference (AR): Book 55, Hadith 394 (AR)
Arabic reference (AR): Book 56, Hadith 412 (AR)