Volume 2 Book 20 Hadith 188

Volume 2, Book 20, Number 188:
Narrated ‘Abdullah bin ‘Umar:
I offered the prayer with the Prophet, Abu Bakr and ‘Umar at Mina and it was of two Rakat. ‘Uth –
man in the early days of his caliphate did the same, but later on he started praying the full prayer.