http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
Here is the most accurate and richly descriptive picture of American English ever offered in any dictionary. Oxford's American editors drew on our 200-million-word databank of contemporary North American English, plus the unrivaled citation files of the world-renowned Oxford English Dictionary. We started with American evidence -- an unparalleled resource unique to Oxford. Our staff logged more than 50 editor-years, checking every entry and every definition. Oxford's ongoing North American Reading Program, begun in the early 1980s, keeps our lexicographers in touch with fresh evidence of our language and usage--in novels and newspapers, in public records and magazines, and on-line, too