Sahih Muslim Book 004, Hadith Number 1979.
Chapter : Mention of the torment of grave in eclipse prayer.
Asma' bint Abu Bakr said: The Apostle of Allah (may peace be upon him) was one day (i.e. on the day when the sun eclipsed) so perturbed that he (in haste) took hold of the outer garment (of a female member of his family) and it was later on that his (own) cloak was sent to him. He stood in prayer along with people for such a long time that if a man came he did not realise that the Apostle of Allah (may peace be upon him) had observed ruku', as it has been narrated about ruku' in connection with long qiyam.