Al-Kāfi - Volume 4 > Disciplines to Maintain in the State of al-’Ihram
Hadith #2

2ـ عَلِيُّ بْنُ إِبْرَاهِيمَ عَنْ أَبِيهِ عَنْ حَمَّادٍ عَنْ حَرِيزٍ عَنْ أَبِي عَبْدِ الله (عَلَيْهِ السَّلاَم) قَالَ إِذَا اغْتَسَلَ الْمُحْرِمُ مِنَ الْجَنَابَةِ يَصُبُّ عَلَى رَأْسِهِ وَيُمَيِّزُ الشَّعْرَ بِأَنَامِلِهِ بَعْضَهُ مِنْ بَعْضٍ.

2. Ali ibn Ibrahim has narrated from his father from Hammad from Hariz who has said the following: “Abu ‘Abd Allah, ‘Alayhi al-Salam, has said, ‘If one who is in the state of Ihram takes Ghusl (bath) due to sexual relation (because of which Ghusl (bath) is obligatory), he can pour water over his head and separate the hairs from each other with his fingers.’”