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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:2750 – Muḥammad b. ʿAbd al-Aʿlá > Khālid > Shuʿbah Anbʾanā Anas b. Sīrīn > a man Yuqāl Lah ʿAbd al-Malik from his father

the Messenger of Allah used to enjoin (fasting) these days of Al-Bid and he said: "That is (equivalent to) fasting for the whole month." (Using translation from Nasāʾī 2430)  

الكبرى للنسائي:٢٧٥٠ – أَخْبَرَنَا مُحَمَّدُ بْنُ عَبْدِ الْأَعْلَى قَالَ حَدَّثَنَا خَالِدٌ عَنْ شُعْبَةَ أَنبأَنا أَنَسُ بْنُ سِيرِينَ عَنْ رَجُلٍ يُقَالُ لَهُ عَبْدُ الْمَلِكِ يُحَدِّثُ عَنْ أَبِيهِ

أَنَّ رَسُولَ اللهِ ﷺ كَانَ يَأْمُرُ بِهَذِهِ الْأَيَّامِ الثَّلَاثِةِ الْبِيضِ وَيَقُولُ «هُنَّ صِيَامُ الشَّهْرِ»  

See similar narrations below:

Collected by Nasāʾī
nasai:2430 – Muḥammad b. ʿAbd al-Aʿlá > Khālid > Shuʿbah > Anas b. Sīrīn > a man Yuqāl Lah ʿAbd al-Malik from his father

the Messenger of Allah used to enjoin (fasting) these days of Al-Bid and he said: "That is (equivalent to) fasting for the whole month."  

النسائي:٢٤٣٠ – أَخْبَرَنَا مُحَمَّدُ بْنُ عَبْدِ الأَعْلَى قَالَ حَدَّثَنَا خَالِدٌ عَنْ شُعْبَةَ قَالَ أَنْبَأَنَا أَنَسُ بْنُ سِيرِينَ عَنْ رَجُلٍ يُقَالُ لَهُ عَبْدُ الْمَلِكِ يُحَدِّثُ عَنْ أَبِيهِ

أَنَّ رَسُولَ اللَّهِ ﷺ كَانَ يَأْمُرُ بِهَذِهِ الأَيَّامِ الثَّلاَثِ الْبِيضِ وَيَقُولُ هُنَّ صِيَامُ الشَّهْرِ  

nasai:2431 – Muḥammad b. Ḥātim > Ḥibbān > ʿAbdullāh > Shuʿbah > Anas b. Sīrīn > ʿAbd al-Malik b. Abū al-Minhāl from his father

the Prophet commanded them to fast the three days of Al-Bid. He said: "That is (equivalent to) fasting for the whole month."  

النسائي:٢٤٣١ – أَخْبَرَنَا مُحَمَّدُ بْنُ حَاتِمٍ قَالَ أَنْبَأَنَا حِبَّانُ قَالَ أَنْبَأَنَا عَبْدُ اللَّهِ عَنْ شُعْبَةَ عَنْ أَنَسِ بْنِ سِيرِينَ قَالَ سَمِعْتُ عَبْدَ الْمَلِكِ بْنَ أَبِي الْمِنْهَالِ يُحَدِّثُ عَنْ أَبِيهِ

أَنَّ النَّبِيَّ ﷺ أَمَرَهُمْ بِصِيَامِ ثَلاَثَةِ أَيَّامِ الْبِيضِ قَالَ هِيَ صَوْمُ الشَّهْرِ