http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
Readability of alphanumeric characters having various contrast levels as a function of age and illumination mode
Kenneth W. Welsh Paul G. Rasmussen, and John A. Vaughan ; Civil Aeromedical Institute, Federal Aviation Administration, Oklahoma City, Oklahoma.
Prepared under Task number AM-A-77-PHY-93.