Virtues and Merits of the Prophet (pbuh) and his Companions
حَدَّثَنَا أَحْمَدُ بْنُ يُونُسَ، حَدَّثَنَا زُهَيْرٌ، حَدَّثَنَا إِسْمَاعِيلُ، عَنْ أَبِي جُحَيْفَةَ ـ رضى الله عنه ـ قَالَ رَأَيْتُ النَّبِيَّ صلى الله عليه وسلم وَكَانَ الْحَسَنُ يُشْبِهُهُ.Narrated Abu Juhaifa:I saw the Prophet, and Al-Hasan resembled him
From Sahih al-Bukhari, whose reports the scholars accept as authentic.