This class represents the geographic coordinate system dictionary. This is definitively detailed in:.

The ISO PDF Specification, ISO 32000-2:2017 PDF 2.0; Table: 270, page 600.

Adobe Supplement to the ISO 32000, BaseVersion: 1.7, ExtensionLevel: 3; Table: 8.111b, page 51.

System.Object
    WebSupergoo.ABCpdf14.Elements.Element
       WebSupergoo.ABCpdf14.Elements.GeographicCoordinateSystemElement

A geographic coordinate system dictionary describes the datum and coordinate reference system used to interpret geographic coordinates in a geospatial PDF. The EPSG entry provides a numeric code identifying the CRS. The WKT entry provides the full Well Known Text definition as a fallback.