‏الصلاة : Hadeeth No:1465 Musa b. Salama Hudhali said: I asked Ibn 'Abbas: How should I say prayer when I am in Mecca, and when I do not pray along with the Imam? He said: Two rak'ahs (of prayer) is the Sunnah of Abu'l-Qasim (sallAllaahu alayhi wa sallam)....

‏الإمارة : Hadeeth No:4556 The same tradition has been narrated by the same authority through another chain of transmitters with a slight difference in wording....