| − | A '''dune''' is a low [[hill]] of drifted [[sand]] in [[coast]]al areas that can be bare or covered with [[vegetation]].<ref>USGS</ref> | + | A '''dune''' is a low [[hill]] of drifted [[sand]] in [[coast]]al areas that can be bare or covered with [[vegetation]].<ref>http://www.nwrc.usgs.gov/fringe/glossary.html</ref> |