The Book of Prayer - Friday
وَحَدَّثَنَا مُحَمَّدُ بْنُ رُمْحٍ، أَخْبَرَنَا اللَّيْثُ، عَنْ يَحْيَى بْنِ سَعِيدٍ، عَنْ عَمْرَةَ، عَنْ عَائِشَةَ، أَنَّهَا قَالَتْ كَانَ النَّاسُ أَهْلَ عَمَلٍ وَلَمْ يَكُنْ لَهُمْ كُفَاةٌ فَكَانُوا يَكُونُ لَهُمْ تَفَلٌ فَقِيلَ لَهُمْ لَوِ اغْتَسَلْتُمْ يَوْمَ الْجُمُعَةِ .Aisha reported:The people (mostly) were workers and they had no servants. Ill-smell thus emitted out of them. It was said to them: Were you to take bath on Friday
From Sahih Muslim, whose reports the scholars accept as authentic.