Sunan Ibn Majah, Hadith 1657 ⓘ
It was narrated from Muhammad bin Sa’d bin Abu Waqqas that his father said: “The Messenger of Allah said: ‘The month is like that and like that and like that,’ and he showed nine fingers on the third time to indicate twenty-nine.”
حَدَّثَنَا مُحَمَّدُ بْنُ عَبْدِ اللَّهِ بْنِ نُمَيْرٍ، حَدَّثَنَا مُحَمَّدُ بْنُ بِشْرٍ، عَنْ إِسْمَاعِيلَ بْنِ أَبِي خَالِدٍ، عَنْ مُحَمَّدِ بْنِ سَعْدِ بْنِ أَبِي وَقَّاصٍ، عَنْ أَبِيهِ، قَالَ قَالَ رَسُولُ اللَّهِ ـ صلى الله عليه وسلم ـ " الشَّهْرُ هَكَذَا وَهَكَذَا وَهَكَذَا " . وَعَقَدَ تِسْعًا وَعِشْرِينَ فِي الثَّالِثَةِ .
also referenced under: Book 7, Hadith 1726 (In-Book) & Volume 2, Book 7, Hadith 1657 (DarusSalam)