حَدَّثَنِي يَحْيَى، عَنْ مَالِكٍ، عَنْ عَبْدِ الْكَرِيمِ بْنِ مَالِكٍ الْجَزَرِيِّ، عَنْ عَبْدِ الرَّحْمَنِ بْنِ أَبِي لَيْلَى، عَنْ كَعْبِ بْنِ عُجْرَةَ، أَنَّهُ كَانَ مَعَ رَسُولِ اللَّهِ صلى الله عليه وسلم مُحْرِمًا فَآذَاهُ الْقَمْلُ فِي رَأْسِهِ فَأَمَرَهُ رَسُولُ اللَّهِ صلى الله عليه وسلم أَنْ يَحْلِقَ رَأْسَهُ وَقَالَ ‏"‏ صُمْ ثَلاَثَةَ أَيَّامٍ أَوْ أَطْعِمْ سِتَّةَ مَسَاكِينَ مُدَّيْنِ مُدَّيْنِ لِكُلِّ إِنْسَانٍ أَوِ انْسُكْ بِشَاةٍ أَىَّ ذَلِكَ فَعَلْتَ أَجْزَأَ عَنْكَ ‏"‏ ‏.‏

Yahya related to me from Malik from Abd al-Karim ibn Malik al-Jazari from Abd ar-Rahman ibn Abi Layla from Kab ibn Ujra that onetime he was with the Messenger of Allah, may Allah bless him and granthim peace, in ihram, and he was suffering from lice on his head. TheMessenger of Allah, may Allah bless him and grant him peace, told himto shave his head, saying, "Fast three days, or feed six poor people,two mudds for each person, or sacrifice a sheep. If you do any ofthose it will be enough for you." Translation Not Available

Book Ref: Muwatta Imam Malik Book 20 Hadith 943
Web Ref:  Muwatta Imam Malik Book 20 Hadith 246