units.xsd v3.0 draft last updated 2002/04/22 GML 3.0 candidate schema. Copyright (c) 2002 OGC, All Rights Reserved. This schema encodes the Reference Systems (RS_) package in the CRS UML Model. The CS_CRS class is also encoded here, to eliminate the references from operations.xsd to coordinateReferenceSystems.xsd. Basic encoding for objects in CRS model, simplifying AbstracGMLType as needed for CRS objects. To be supplied. Association to a Reference System, either referencing or containing the definition of that Reference System. To be supplied. Association to a Spatial Reference System Using Geographic Identifier, either referencing or containing the definition of that Reference System. The abstract class coordinate reference system consists of a coordinate system and a datum Association to a CRS abstract coordinate reference system, either referencing or containing the definition of that CRS. To be supplied. Character string giving a name or code, optionally from a controlled list or pattern defined by an authority. Identifier of a code space within which one or more codes are defined. This code space is often defined by some authority organization, where one organization may define multiple code spaces. The range and format of each Code Space identifier is defined by that code space authority. Identifier of the version of the associated codeSpace or code, as specified by the codeSpace or code authority. When appropriate, the edition is identified by the effective date, coded using ISO 8601 date format. Organization or party responsible for definition and maintenance of the code space or name space. The name by which this object is identified. Comments on or information about this object, including data source information. Alternative name or identifier by which this object is known. An alias of this object. Identifier of namespace that this alias name is defined in; for example, "ISO 2-char country code" or "EPSG abbreviation". Remarks relating to this alias. Extended identification and description information for a CRS object. Validity area or region for which this object is valid. Description of domain of usage, or limitations of usage, for which this object is valid.