Yahya related to me from Malik from Ibn Shihab that Zayd ibnThabit said, "When a man takes his wife to his house and co-habitswith her then the bride-price is obliged." (RU)
USC-MSA web (English) reference: Book 28, Hadith 13 (RU)
Arabic reference (RU): Book 28, Hadith 1106 (RU)