Abdullah bin Abi Qatadah (may Allah have mercy on him) narrates from his father (may Allah be pleased with him) that the Prophet (peace and blessings be upon him) used to recite Surah al-Fatihah and two surahs in the first two rak'ahs of Zuhr and Asr, and in the last two rak'ahs he recited Surah al-Fatihah. Sometimes he would let us hear a verse. He (peace and blessings be upon him) would make the first rak'ah long and the second somewhat shorter, and he did the same in the Asr and Fajr prayers.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 2485