http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
Operational navigation chart, ONC, [North America]
prepared under the direction of the Department of Defense.
Relief shown by contours, tints, and spot heights.
"Air information current through 18 April 1972".
"Base information compiled September 1963, revised May 1969 (NOS)".
Includes terrain characteristic tints and interchart relationship diagrams.
Lambert conformal conic proj., standard parallels 49⁰20ʹ and 54⁰40ʹ