The term 'Gospel Author' refers to the authors of the four Gospels in the New Testament of the Bible. The four authors are MARK, Luke, St. MARK, and Saint Luke. MARK is traditionally believed to be the author of the Gospel of MARK, while Luke is traditionally believed to be the author of the Gospel of Luke. St. MARK and Saint Luke are alternative names for the same authors, with St. MARK being a shortened version of Saint MARK and Saint Luke being a shortened version of Saint Luke.