(4) باب الشَّهْرِ يَكُونُ تِسْعًا وَعِشْرِينَ
Narrated Abdullah ibn Mas'ud:
We kept fast for twenty-nine days along with the Prophet (ﷺ) more often than we kept fast for thirty days. (PT)
Reference (PT): Sunan Abi Dawud 2322 (PT)
In-book reference (PT): Book 14, Hadith 10 (PT)
English translation (PT): Book 13, Hadith 2315 (PT)