The projection and coordinate system for the original map were not given. It was necessary to georeference the map to real world coordinates. This was done as follows:1. The latitude/longitude grid with cell size 4 * 6 degrees was projected to Equidistant Conic projection and then used to create ARC/INFO point coverage. That point coverage was used to create "to -from" links by ARC/INFO CONTROLPOINTS program.2. A gray-scale scanned image of the original paper map was transformed to Equidistant Conic projection by ARC/INFO GRIDWARP program (polynomial of the second order) using the "to -from" links created by CONTROLPOINTS program.3. The scanned image from the second step was vectorized by the method of extraction of linear features described by F.Persits, 1997, (USGS open-file report OF-97-713), and then corrected by hands-on digitization.4. A series of piecewise "rubbersheet" transformations applied to the final ARC/INFO coverage. The ARC/INFO coverages that were used for transformation were ESRI's ArcWorld 1:3M GIS cartographic layers (RIV3M, CTRY3M).
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