Sahih Muslim 749hBook 6, Hadith 191
وَحَدَّثَنَا ابْنُ الْمُثَنَّى، وَابْنُ، بَشَّارٍ قَالاَ حَدَّثَنَا مُحَمَّدُ بْنُ جَعْفَرٍ، حَدَّثَنَا شُعْبَةُ، عَنْ أَنَسِ بْنِ سِيرِينَ، قَالَ سَأَلْتُ ابْنَ عُمَرَ . بِمِثْلِهِ وَزَادَ وَيُوتِرُ بِرَكْعَةٍ مِنْ آخِرِ اللَّيْلِ . وَفِيهِ فَقَالَ بَهْ بَهْ إِنَّكَ لَضَخْمٌ .
I asked Ibn 'Umar like this (as recorded in the previous hadith) and he made this addition:" And he (the Holy Prophet) made the end of the night prayer as odd number by one rak'ah." And there is also (this addition):" Stop, stop, you are bulky."