There is a Hadith in Jame’ Tirmidhi:
Translation of Hadith: It has been narrated on the authority of Hadhrat Jabir Bin Abdullah (May Allah Ta’ala be well pleased with him) that he said: The Salaat of a person who does not recite Surah Fatiha is invalid, but this rule is for the person WHO IS NOT a Muqtadi under an Imam. Imam Tirmidhi has recorded this Hadith and has declared it as Hasan-Sahih (fairly authenticated). Also, Imam Muhammad, Imam Malik and Ibn Abi Shaiba have also recorded this Hadith. (Jame’ Tirmidhi, Hadith No: 288; Zujajatul Masabeeh, Vol. 1, Pg No: 245)
There is a Hadith in Sunan Nasai, Jame’ Tirmidhi, Sunan Abu Dawood, Musnad Imam Ahmed and Zujajatul Masabeeh:
Translation of Hadith: It has been narrated on the authority of Hadhrat Abu Hurairah (May Allah Ta’ala be well pleased with him) that after a Salaat in which there is loud Qiraat, the Holy Prophet (Sallallahu alaihi wa sallam) said after finishing the Salaat: Was anyone from you reciting the Holy Quran along with me? A person said: Yes! O Prophet of Allah (Sallallahu alaihi wa sallam), I was reciting. The Holy Prophet (Sallallahu alaihi wa sallam) said: That is why, I was just thinking, why in the Salaat (recitation of) the Holy Quran was being mixed up.