Not graded
Sunan ad-Darimi 938
أَخْبَرَنَا مُحَمَّدُ بْنُ يُوسُفَ حَدَّثَنَا سُفْيَانُ عَنْ ابْنِ جُرَيْجٍ عَنْ عَطَاءٍ قَالَ النِّفَاسُ حَيْضٌ
This hadith has no English translation yet: the Arabic text, the reference and the grade are shown here.
Reported by Ad-Darimi (No. 938).