Muwatta 1590

Malik says of a man who tells his wife: you are khaliyya, or bariyya, or ba'in. For a wife he has consummated, it is three divorces. For one he has not consummated, the words are taken on his intention, one or three. If he says one, he swears to it, and he is then one of the ordinary suitors. A consummated wife cannot be freed, cleared or separated except by three divorces, while one not consummated is freed, cleared and separated by one. Malik said this is the best of what he has heard on the matter. ¹

Belongs to the Muwatta, Book of Divorce. Source: the Muwatta. Mentions Malik ibn Anas. Built on in the chapters on divorce.