Sunan Abi Dawud, Hadith 6 ⓘ
Narrated Zayd ibn Arqam: The Messenger of Allah said: These privies are frequented by the jinns and devils. So when anyone amongst you goes there, he should say: "I seek refuge in Allah from male and female devils."
حَدَّثَنَا عَمْرُو بْنُ مَرْزُوقٍ، أَخْبَرَنَا شُعْبَةُ، عَنْ قَتَادَةَ، عَنِ النَّضْرِ بْنِ أَنَسٍ، عَنْ زَيْدِ بْنِ أَرْقَمَ، عَنْ رَسُولِ اللَّهِ صلى الله عليه وسلم قَالَ " إِنَّ هَذِهِ الْحُشُوشَ مُحْتَضَرَةٌ فَإِذَا أَتَى أَحَدُكُمُ الْخَلاَءَ فَلْيَقُلْ أَعُوذُ بِاللَّهِ مِنَ الْخُبُثِ وَالْخَبَائِثِ " .
also referenced under: Hadith 6 (DarusSalam) & Book 1, Hadith 6 (USC-MSA)