Narrated [Abu Hurairah (RA)]:

When Allah's Messenger (RA) completed the recitation of Surat Al-Fatiha, he raised his voice and said Amin. [Reported by ad-Daraqutni who graded it Hasan (good) and Al-Hakim who graded it Sahih (authentic)).

وَعَنْهُ قَالَ : { كَانَ رَسُولُ اَللَّهِ ‏- صلى الله عليه وسلم ‏-إِذَا فَرَغَ مِنْ قِرَاءَةِ أُمِّ اَلْقُرْآنِ رَفَعَ صَوْتَهُ وَقَالَ :

آمِينَ

.‏ } رَوَاهُ اَلدَّارَقُطْنِيُّ وَحَسَّنَهُ , وَالْحَاكِمُ وَصَحَّحَهُ .‏ [1]‏ .‏