The month may be twenty-nine days Sahih Muslim 1086 b
Arabic hadith text
وَحَدَّثَنِي الْقَاسِمُ بْنُ زَكَرِيَّاءَ، حَدَّثَنَا حُسَيْنُ بْنُ عَلِيٍّ، عَنْ زَائِدَةَ، عَنْ إِسْمَاعِيلَ، عَنْ مُحَمَّدِ بْنِ سَعْدٍ، عَنْ أَبِيهِ، - رضى الله عنه - عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ "الشَّهْرُ هَكَذَا وَهَكَذَا وَهَكَذَا " . عَشْرًا وَعَشْرًا وَتِسْعًا مَرَّةً .
Translation
Muhammad b. Sa'd reported on the authority of his father (Sa'd b. Abi Waqqas (Allah be pleased with him) that the Messenger of Allah (ﷺ) had said
Tho month is thus and thus, and thus, i. e. ten, ten and nine.