The Book of the Merits of the Companions
حَدَّثَنَا مُحَمَّدُ بْنُ الْمُثَنَّى، حَدَّثَنَا أَبُو دَاوُدَ، حَدَّثَنَا شُعْبَةُ، عَنْ قَتَادَةَ، سَمِعْتُ أَنَسًا، يَقُولُ قَالَتْ أُمُّ سُلَيْمٍ يَا رَسُولَ اللَّهِ خَادِمُكَ أَنَسٌ . فَذَكَرَ نَحْوَهُ .Anas reported (that his mother) Umm Sulaim said (to the Holy Prophet) Allah's Messenger, here is your servant Anas. The rest of the hadith is the same
From Sahih Muslim, whose reports the scholars accept as authentic.