Not graded
Sunan ad-Darimi 1155
أَخْبَرَنَا يَزِيدُ حَدَّثَنَا شَرِيكٌ عَنْ لَيْثٍ عَنْ طَاوُسٍ فِي اسْتِبْرَاءِ الْأَمَةِ إِنْ لَمْ تَكُنْ تَحِيضُ قَالَ خَمْسَةً وَأَرْبَعِينَ
This hadith has no English translation yet: the Arabic text, the reference and the grade are shown here.
Reported by Ad-Darimi (No. 1155).