(6) باب مَا جَاءَ أَنَّ الشَّهْرَ يَكُونُ تِسْعًا وَعِشْرِينَ
Anas narrated:
"The Messenger of Allah vowed to stay away from his wives for a month, so he stayed in a loft for twenty-nine days. They said: 'O Messenger of Allah, your vow was for a month,' so he said: 'The month is twenty-nine (days).'"
Reference: Jami` at-Tirmidhi 690
In-book reference: Book 8, Hadith 9
English translation: Vol. 2, Book 3, Hadith 690