Abu Dawud Book 2, Hadith Number 1273.
Chapter : The view that the praying of the two rakahs after the afternoon prayer is permissible when the sun is at its height.
Narated By Abdullah ibn Umar : Yasar, the client of Ibn Umar, said: Ibn Umar saw me praying after the break of dawn. He said: O Yasar, the Apostle of Allah (PBUH) came to us while we were offering this prayer. He (the Prophet) said: Those who are present should inform those who are absent: Do not offer any prayer after (the break of) dawn except two rak’ahs.