Bulugh al-Maram, Book 1, Hadith 172 (In-Book)

Narrated Umm `Atiyah (RAA): After we were pure, we did not consider the yellow or muddy discharge to be anything (i.e. of the menses blood) [Reported by Al-Bukhari and Abu Dawud and the wording is of Abu Dawud].

وَعَنْ أُمِّ عَطِيَّةَ رَضِيَ اَللَّهُ عَنْهَا قَالَتْ: { كُنَّا لَا نَعُدُّ اَلْكُدْرَةَ وَالصُّفْرَةَ بَعْدَ اَلطُّهْرِ شَيْئًا } رَوَاهُ اَلْبُخَارِيُّ, وَأَبُو دَاوُدَ وَاللَّفْظُ لَه ُ (171)‏.‏ ‏1 ‏- صحيح.‏ وهو موقوف.‏ رواه البخاري (326)‏، وأبو داود (307)‏.‏

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also referenced under: Book 1, Hadith 154 (English)