أَخْبَرَنَا عُبَيْدُ اللَّهِ بْنُ سَعِيدٍ، قَالَ حَدَّثَنَا يَحْيَى بْنُ سَعِيدٍ، عَنْ عَبْدِ الرَّحْمَنِ بْنِ عَمَّارٍ، قَالَ حَدَّثَنِي الْقَاسِمُ بْنُ مُحَمَّدٍ، عَنْ عَائِشَةَ، عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ " صَلاَةُ الْجَمَاعَةِ تَزِيدُ عَلَى صَلاَةِ الْفَذِّ خَمْسًا وَعِشْرِينَ دَرَجَةً " .
It was narrated from that the Prophet (PBUH) said: "Prayer in congregation is twenty-five levels better than a prayer offered on one's own." Translation Not Available
Book Ref: Sunan An Nisai Book 10 Hadith 839
Web Ref: Sunan An Nisai Vol 1 Book 10 Hadith 840