Yahya related to me from Malik from Nafi that Abdullan ibn Umarsaid, "The only place a woman whose husband has died and a woman whois absolutely divorced can spend the night is in their houses." (RU)
USC-MSA web (English) reference: Book 29, Hadith 90 (RU)
Arabic reference (RU): Book 29, Hadith 1254 (RU)