What is the evidence for the sufficiency of reciting only Surah Al-Fatihah in the third and fourth rak'ahs (cycles of prayer), and in the third rak'ah of Maghrib prayer?

The Prophet (peace be upon him) used to recite Al-Fatihah in the last two rak'ahs of Dhuhr and Asr prayers. Scholars have appended to these the third rak'ah of Maghrib and the third and fourth rak'ahs of Isha. It is authentically reported in the hadith of Abu Sa'id that the Prophet (peace be upon him) sometimes recited more than just Al-Fatihah in the third and fourth rak'ahs of Dhuhr. As for Maghrib, there is no harm in reciting the verse, "Our Lord, let not our hearts deviate after You have guided us and grant us from Yourself mercy. Indeed, You are the Bestower" [Quran 3:8] in the third rak'ah. However, there is also no harm in omitting it, as it was not reported from the Prophet (peace be upon him). As for Isha, there is no evidence for adding more than Al-Fatihah in the third and fourth rak'ahs; therefore, one should not add anything more than Al-Fatihah in them.