Michel Maittaire (1667–1747) and Georg Wolfgang Panzer (1729–1805) arranged printed material chronologically in annals format, and in the first half of the 19th century, Ludwig Hain published the Repertorium bibliographicum— a checklist of incunabula arranged alphabetically by author: "Hain numbers" are still a reference point. Hain was expanded in subsequent editions, by Walter A. Copinger and Dietrich Reichling, but it is being superseded by the authoritative modern listing, a German catalogue, the Gesamtkatalog der Wiegendrucke, which has been under way since 1925 and is still being compiled at the Staatsbibliothek zu Berlin. North American holdings were listed by Frederick R. Goff and a worldwide union catalogue is provided by the Incunabula Short Title Catalogue.[31]