Origen y desarrollo del problema del transporte urbano y las diversas reacciones populares

An unparalleled archive of gray literature (published and unpublished documents, pronouncements, action alerts, press releases, flyers, newsclippings, correspondence, and other types of ephemeral material), serials, and policy reports representing the actions and views of activist groups, government officers and politicians, journalists, international solidarity groups, as well as revolutionary organizations. Princeton University Library acquired the archive in 2002 and subsequently digitized over 14,000 items from the Ephemera Section of the archive with the support of the Cooperative Digitization of International Research Materials (CDIRM) project, organized by the Council of American Overseas Research Centers (CAORC).