Sahih Muslim Book 4, Hadith Number 1819.

Chapter : How Amr b. Abasa embraced Islam.

Aswad and Masruq reported: We bear testimony to the fact that ‘Aisha said: Never was there a day that he (the Holy Prophet) was with me and he did not observe two rak’ahs of prayer in my house, i.e. two rak’ahs after the Asr.