http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
National air quality status and trends through
U.S. Environmental Protection Agency, Office of Air Quality Planning and Standards, Air Quality Assessment Division
In scope of the U.S. Government Publishing Office Cataloging and Indexing Program (C&I) and Federal Depository Library Program (FDLP).
GPO Cataloging Record Distribution Program (CRDP).
Latest findings on national air quality (Online)