Sahih Al Bukhari Hadith Number 759

Narrated `Abdullah bin Abi Qatada: My father said, “The Prophet (peace be upon him) in Zuhr prayers used to recite Al-Fatiha along with two other Suras in the first two rak`at: a long one in the first rak`a and a shorter (Sura) in the second, and at times the verses were audible. In the `Asr prayer the Prophet (peace be upon him) used to recite Al-Fatiha and two more Suras in the first two rak`at and used to prolong the first rak`a. And he used to prolong the first rak`a of the Fajr prayer and shorten the second.

10  Call to Prayers (Adhaan)
Hadith number 759
Volume no 1
Chapter: 96 (The recitation of the Qur’an in a Zuhr prayer)