http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
9th ed., Dec. , 2008, corrected through NM Dec. 20, 2008, LNM Dec. 16, 2008.
Relief shown by contours and spot heights.
"Soundings in fathoms (fathoms and feet to 11 fathoms)."
Includes source diagram and tidal information.