http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
Also available via Internet from the NTRS web site. Address as of 5/9/05: http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19910008299%5F1991008299.pdf; current access is available via PURL.
Microfiche. [Washington, D.C. : National Aeronautics and Space Administration,] 1991. 1 microfiche.