Narrated `Abdullah bin `Umar: I offered the prayer with the Prophet, Abu Bakr and `Umar at Mina and it was of two rak`at. `Uthman in the early days of his caliphate did the same, but later on he started praying the full prayer.
Hadith Referenceصحيح البخاري / كتاب تقصير الصلاة / 1082
Hadith Gradingمحدثین:أحاديث صحيح البخاريّ كلّها صحيحة
Narrated `Abdur Rahman bin Yazid: We offered a four rak`at prayer at Mina behind Ibn `Affan . `Abdullah bin Mas`ud was informed about it. He said sadly, "Truly to Allah we belong and truly to Him we shall return." And added, "I prayed two rak`at with Allah's Apostle at Mina and similarly with Abu Bakr and with `Umar (during their caliphates)." He further said, "May I be lucky enough to have two of the four rak`at accepted (by Allah)."
Hadith Referenceصحيح البخاري / كتاب تقصير الصلاة / 1084
Hadith Gradingمحدثین:أحاديث صحيح البخاريّ كلّها صحيحة