Most scholars hold to the two-source hypothesis, which posits that the Gospel of Mark was the first gospel to be written. On this view, the authors of the Gospel of Matthew and the Gospel of Luke used as sources the Gospel of Mark and a hypothetical Q document to write their individual gospel accounts. These three gospels are called the Synoptic Gospels, because they include many of the same stories, often in the same sequence, and sometimes in exactly the same wording. Scholars agree that the Gospel of John was written last, by using a different tradition and body of testimony. In addition, most scholars agree that the author of Luke also wrote the Acts of the Apostles. Scholars hold that these books constituted two-halves of a single work, Luke–Acts.