The Book of Marriage (Kitab Al-Nikah)
Muslim :: Book 8 : Hadith 3445
Abu Bakr b. 'Abd al-Rahman reported that when Allah's Messenger (may peace be upon him) married Umm Salama and he visited her, and when he intended to come out, she caught hold of his cloth. whereupon Allah's Messenger (may peace be upon him) said: If you so desire, I can extend the time (of my stay) with you, but then I shall have to calculate the time (that I stay with you and shall have to spend the same time with other wives). For the virgin woman, (her husband has to stay with her) for a week, and for the woman previously married it is three days.