Sahih Bukhari
Sahih Bukhari Volume 001, Book 012, Hadith Number 778.
Hadith Section/Book: Sahih Bukhari Sahih Bukhari Book 12. Charecteristics Of Prayer
Narated By Sahl bin Sa'd : The people used to pray with the Prophet tying their Izars around their necks because of their small sizes and the women were directed that they should not raise their heads from the prostrations till the men had sat straight.