وَحَدَّثَنِي عَنْ مَالِكٍ، عَنْ جَعْفَرِ بْنِ مُحَمَّدٍ، عَنْ أَبِيهِ، أَنَّهُ قَالَ وَزَنَتْ فَاطِمَةُ بِنْتُ رَسُولِ اللَّهِ صلى الله عليه وسلم شَعَرَ حَسَنٍ وَحُسَيْنٍ وَزَيْنَبَ وَأُمِّ كُلْثُومٍ فَتَصَدَّقَتْ بِزِنَةِ ذَلِكَ فِضَّةً ‏.‏

Yahya related to me from Malik from Jafar ibn Muhammad that hisfather said, "Fatima, the daughter of the Messenger of Allah, mayAllah bless him and grant him peace, weighed the hair of Hasan,Husayn, Zaynab and Umm Kulthum, and gave away in sadaqa an equivalentweight of silver." Translation Not Available

Book reference: Muwatta Imam Malik Book 26 Hadith 1071
Web reference: Muwatta Imam Malik Book 26 Hadith 2