U.S.Department of the Interior, U.S.Geological Survey, 1990, Standards for Digital Line Graphs, Part 1: General: Reston, VA, 1994
U.S.Department of the Interior, U.S.Geological Survey, 1990, Standards for Digital Line Graphs, Part 2: Specifications: Reston, VA, 1994
U.S.Department of the Interior, U.S.Geological Survey, 1990, Standards for Digital Line Graphs, Part 3: Attribute Codes: Reston, VA, 1994
A hypertext extract is available at: URL: <http://edc.usgs.gov/glis/hyper/guide/usgs_dlg>
Softcopies in ASCII, WordPerfect, and PostScript format are available at: URL: <ftp://mapping.usgs.gov/pub/ti/DLG/>
Softcopies in ASCII, WordPerfect, and PostScript format are available at: URL: <ftp://mapping.usgs.gov/pub/ti/DLG/>