كتاب الحيض
3  
The Book of Menstruation
(6)
Chapter: It is permissible for one who is junub to sleep, but it is recommended for him to perform wudu’, and wash his private parts if he wants to eat, drink, sleep, or have intercourse
(6)
باب جَوَازِ نَوْمِ الْجُنُبِ وَاسْتِحْبَابِ الْوُضُوءِ لَهُ وَغَسْلِ الْفَرْجِ إِذَا أَرَادَ أَنْ يَأْكُلَ أَوْ يَشْرَبَ أَوْ يَنَامَ أَوْ يُجَامِعَل
Sahih Muslim 305 c

This hadith has been transmitted by Shu'ba with the same chain of transmitters. Ibn at-Muthanna said in his narration:

AI-Hakam narrated to us who heard from Ibrahim narrating that.
حَدَّثَنَا مُحَمَّدُ بْنُ الْمُثَنَّى، وَابْنُ، بَشَّارٍ قَالاَ حَدَّثَنَا مُحَمَّدُ بْنُ جَعْفَرٍ، ح وَحَدَّثَنَا عُبَيْدُ اللَّهِ بْنُ مُعَاذٍ، قَالَ حَدَّثَنَا أَبِي قَالَ، حَدَّثَنَا شُعْبَةُ، بِهَذَا الإِسْنَادِ قَالَ ابْنُ الْمُثَنَّى فِي حَدِيثِهِ حَدَّثَنَا الْحَكَمُ، سَمِعْتُ إِبْرَاهِيمَ، يُحَدِّثُ ‏.‏
Reference : Sahih Muslim 305c
In-book reference : Book 3, Hadith 23
USC-MSA web (English) reference : Book 3, Hadith 599
  (deprecated numbering scheme)