Bathing (Ghusl) 
Bukhari :: Book 1 :: Volume 5 :: Hadith 285
Narrated 'Umar bin Al-Khattab:
I asked Allah's Apostle "Can any one of us sleep while he is Junub?" He replied, "Yes, if he performs ablution, he can sleep while he is Junub."
Bathing (Ghusl)
Bukhari :: Book 1 :: Volume 5 :: Hadith 285
Narrated 'Umar bin Al-Khattab:
I asked Allah's Apostle "Can any one of us sleep while he is Junub?" He replied, "Yes, if he performs ablution, he can sleep while he is Junub."