Sahih Muslim Book 003, Hadith Number 0714.
Chapter : Tayammum.
'Aisha reported: We went with the Apostle of Allah (may peace be upon him) on one of his journeys and when we reached the place Baida' or Dhat al-jaish, my necklace was broken (and fell somewhere). The Messenger of Allah (way peace be upon him) along with other people stayed there for searching it. There was neither any water at that place nor was there any water with them (the Companions of the Holy Prophet). Some persons came to my father Abu Bakr and said: Do you see what 'Aisha has done? She has detained the Messenger of Allah (may peace be upon him) and persons accompanying him, and there is neither any water here or with them. So Abu Bakr came there and the Messenger of Allah (may peace be upon him) was sleeping with his head on my thigh. He (Abu Bakr) said: You have detained the Messenger of Allah (may peace be upon him) and other persons and there is neither water here nor with them. She ('Aisha) said: Abu Bakr scolded me and uttered what Allah wanted him to utter and nudged my hips with his hand. And there was nothing to prevent me from stirring but for the fact that the messenger of Allah (may peace be upon him) was lying upon my thigh. The Messenger of Allah (may peace be upon him) slept till it was dawn at a waterless place. So Allah revealed the verses pertaining to tayammum and they (the Holy Prophet and his Companions) performed tayammum. Usaid b. al-Hudair who was one of the leaders said: This is not the first of your blessings, O Family to Abu Bakr. 'Aisha said: We made the case) stand which was my mount and found the necklace under it.