Abu Dawud Book 14, Hadith Number 3214.
Chapter : Not known.
Narated By Al-Qasim ibn Muhammad ibn AbuBakr : I said to ‘Aisha! Mother, show me the grave of the Apostle of Allah (PBUH) and his two Companions (Allah be pleased with them). She showed me three graves which were neither high nor low, but were spread with soft red pebbles in an open space.