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Qurʾān Bukhārī Muslim Nasāʾī Abū Dāwūd Tirmidhī Ibn Mājah Mālik Aḥmad Dārimī Ḥākim Ibn Ḥibbān Ṭabarānī Nasāʾī's Kubrá Bayhaqī al-Luʾluʾ wa-al-Marjān Ibn Rajab's Fifty Riyāḍ al-Ṣāliḥīn Aḥmad's Zuhd Suyūṭī
nasai-kubra:2731 – Muḥammad b. Ḥātim > Ḥibbān > ʿAbdullāh > ʿĀṣim > Abū ʿUthmān > a man > Abū Dhar

"I heard the Messenger of Allah say: "Whoever fasts three days of each month has fasted the month in full' or 'will have (the reward of) fasting the month."' 'Asim was in doubt. (Using translation from Nasāʾī 2410)  

الكبرى للنسائي:٢٧٣١ – أَخْبَرَنَا مُحَمَّدُ بْنُ حَاتِمٍ قَالَ حَدَّثَنَا حِبَّانُ قَالَ أَخْبَرَنَا عَبْدُ اللهِ عَنْ عَاصِمٍ عَنْ أَبِي عُثْمَانَ عَنْ رَجُلٍ قَالَ قَالَ أَبُو ذَرٍّ

سَمِعْتُ رَسُولَ اللهِ ﷺ يَقُولُ «مَنْ صَامَ ثَلَاثَةَ أَيَّامٍ مِنْ كُلِّ شَهْرٍ فَقَدْ تَمَّ لَهُ صَوْمُ الشَّهْرِ أَوْ فَلَهُ صَوْمُ الشَّهْرِ» شَكَّ عَاصِمٌ  

See similar narrations below:

Collected by Nasāʾī, Suyūṭī
nasai:2410 – Muḥammad b. Ḥātim > Ḥibbān > ʿAbdullāh > ʿĀṣim > Abū ʿUthmān > a man > Abū Dhar

"I heard the Messenger of Allah say: "Whoever fasts three days of each month has fasted the month in full' or 'will have (the reward of) fasting the month."' 'Asim was in doubt.  

النسائي:٢٤١٠ – أَخْبَرَنَا مُحَمَّدُ بْنُ حَاتِمٍ قَالَ أَنْبَأَنَا حِبَّانُ قَالَ أَنْبَأَنَا عَبْدُ اللَّهِ عَنْ عَاصِمٍ عَنْ أَبِي عُثْمَانَ عَنْ رَجُلٍ قَالَ أَبُو ذَرٍّ

سَمِعْتُ رَسُولَ اللَّهِ ﷺ يَقُولُ مَنْ صَامَ ثَلاَثَةَ أَيَّامٍ مِنْ كُلِّ شَهْرٍ فَقَدْ تَمَّ صَوْمُ الشَّهْرِ أَوْ فَلَهُ صَوْمُ الشَّهْرِ شَكَّ عَاصِمٌ