Sahih Bukhari Volume 8, Book 76, Hadith Number 529.

Narated By Abu Huraira : The Prophet said, “The people will be gathered in three ways: (The first way will be of) those who will wish or have a hope (for Paradise) and will have a fear (of punishment), (The second batch will be those who will gather) riding two on a camel or three on a camel or ten on a camel. (The third batch) the rest of the people will be urged to gather by the Fire which will accompany them at the time of their afternoon nap and stay with them where they will spend the night, and will be with them in the morning wherever they may be then, and will be with them in the afternoon wherever they may be then.”