Periodicals Archive Online (most from first issue to 1995; RefWorks help; XLinks) provides the backfiles of periodicals in ancient civilizations, history, humanities, linguistics, literature, philosophy, and religion. Users can search for articles by keyword, author, article title, journal title, language, journal subject, and year. Users can browse journals by title or journal subject. It is produced by Chadwyck-Healey and the user interface is provided by ProQuest.