Produced and maintained by the Transportation Research Board (TRB) at the National Academies of Sciences, "the Transportation Research Information Services (TRIS) Database is the world's largest and most comprehensive bibliographic resource on transportation information." Recently, an online version of TRIS was launched as a component of the National Transportation Library, providing access to over 400,000 bibliographic records covering transportation research published in books, journal articles, technical reports, and other media. The records cover the literature from the 1960s to the present, including federal, state, local, and association publications. Users can search the database by author, title, or keyword, with a number of modifiers. Search returns include title, author, journal title (where applicable), date, an abstract, and where the resource can be obtained. In some instances, links to the full text or sources of the full text are provided.