و حَدَّثَنَا عُبَيْدُ اللَّهِ بْنُ سَعِيدٍ حَدَّثَنَا يَحْيَی بْنُ سَعِيدٍ عَنْ عُبَيْدِ اللَّهِ بِهَذَا الْإِسْنَادِ وَقَالَ ذَکَرَ رَسُولُ اللَّهِ صَلَّی اللَّهُ عَلَيْهِ وَسَلَّمَ رَمَضَانَ فَقَالَ الشَّهْرُ تِسْعٌ وَعِشْرُونَ الشَّهْرُ هَکَذَا وَهَکَذَا وَهَکَذَا وَقَالَ فَاقْدِرُوا لَهُ وَلَمْ يَقُلْ ثَلَاثِينَ
صحیح مسلم · Hadith 2501
This hadith is narrated on the authority of 'Ubaidullah with the same chain of transmitters, and he said: If (the sky) is cloudy for you, then calculate thirty days (for the month of Ramadan).
Translated by Dr. Muhammad Muhsin Khan · Reviewed by Islamic University of Madinah · Published March 2020