Sahih al-Bukhari, Volume 2, Book 13, Hadith 20 (USC-MSA) ⓘ
Narrated Abu Sa`id Al-Khudri: Allah's Messenger said, "The taking of a bath on Friday is compulsory for every Muslim who has attained the age of puberty."
حَدَّثَنَا عَبْدُ اللَّهِ بْنُ مَسْلَمَةَ، عَنْ مَالِكٍ، عَنْ صَفْوَانَ بْنِ سُلَيْمٍ، عَنْ عَطَاءِ بْنِ يَسَارٍ، عَنْ أَبِي سَعِيدٍ الْخُدْرِيِّ ـ رضى الله عنه ـ أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ " غُسْلُ يَوْمِ الْجُمُعَةِ وَاجِبٌ عَلَى كُلِّ مُحْتَلِمٍ " .
also referenced under: Book 11, Hadith 20 (In-Book) & Hadith 895 (DarusSalam)