We analysed the historic maps and applied appropriate numerical
descriptors. The 1912 map was scanned and georeferenced.
Five ground control points were selected among road intersections
and river confluences that were represented consistently over time.
By using ESRI ArcGIS 10.1 tools, we assessed the accuracy of the
georeferencing process. Specifically, we used the first order polynomial transformation type to compute the RMS (Root Mean
Square), which had a value of 1.895