Bulugh al-Maram, Book 6, Hadith 788 (English)

Ibn Abbas (RAA) narrated that the Messenger of Allah said: "Women (pilgrims) do not have to shave (their heads); they may only shorten their hair." Related by Abu Dawud with a good chain of narrators.

وَعَنِ اِبْنِ عَبَّاسٍ رَضِيَ اَللَّهُ عَنْهُمَا, عَنِ اَلنَّبِيِّ ‏- صلى الله عليه وسلم ‏-قَالَ: { لَيْسَ عَلَى اَلنِّسَاءِ حَلْقٌ, وَإِنَّمَا يُقَصِّرْنَ } رَوَاهُ أَبُو دَاوُدَ بِإِسْنَادٍ حَسَنٍ 1‏.‏ ‏1 ‏- حسن.‏ رواه أبو داود ( 1985 )‏، وقواه أبو حاتم في " العلل " ( 1 / 281 / 1431 )‏.‏

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also referenced under: Book 6, Hadith 61 (In-Book)