Low-resolution outlines of lakes and inland seas worldwide, stored as
polygons in shapefile format with coordinates in latitude (Y) and
longitude (X) in degrees.  A 'Name' attribute provides a names for each
lake or sea.  The coordinate sampling is equivalent to a scale of
1:30,000,000.  This data set is suitable for global displays.

Source
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The raw coordinate data were derived from the Digital Chart of the World
(DCW) browser layer, published by U.S. National Geospatial-Intelligence
Agency (NGA), formerly National Imagery and Mapping Agency (NIMA).