Sahih Bukhari Volume 7, Book 72, Hadith Number 824.

Narrated By Asma’ : A woman asked the Prophet saying, “0 Allah’s Apostle! My daughter got measles and her hair fell out. Now that I got her married, may I let her use false hair?” He said (to her), “Allah has cursed the lady who lengthens hair artificially and the one who gets her hair lengthened artificially.”