Sahih Bukhari Volume 2, Book 23, Hadith Number 474.

Narated By ‘Urwa : When the wall fell on them (i.e. graves) during the caliphate of Al-Walid bin ‘Abdul Malik, the people started repairing it, and a foot appeared to them. The people got scared and thought that it was the foot of the Prophet. No-one could be found who could tell them about it till I (‘Urwa) said to them, “By Allah, this is not the foot of the Prophet but it is the foot of Umar.” ‘Aisha narrated that she made a will to ‘Abdullah bin Zubair, “Do not bury me with them (the Prophet and his two companions) but bury me with my companions (wives of the Prophet (p.b.u.h)) in Al-Baqi as I would not like to be looked upon as better than I really am (by being buried near the Prophet).”