<xsd:attributeGroup id="attGp.fromContext" name="fromContext">
    <xsd:attribute id="att.fromContext" name="fromContext" type="idType">
        <xsd:annotation>
            <xsd:documentation>
                <h:div class="summary" xmlns:h="http://www.w3.org/1999/xhtml">The context for the 'from' links in a map.</h:div>
                <h:div class="description" xmlns:h="http://www.w3.org/1999/xhtml">
                    <h:p>A reference to the unique 'id' attribute of an element defining the context for links in a map. This may be required when id attributes may not be unique within a document. The id should either reference an element uniquely or should be taken as the first ancestor (of the map) with such an id.</h:p>
                    <h:p>This is fairly horrid but may be required when documents are assembled without establishing unique ids (e.g. concatenation of files). As an example a map referencing linked atoms in two molecules might use the containing 'reaction' element as its uniquifying context.</h:p>
                </h:div>
                <h:div class="curation" xmlns:h="http://www.w3.org/1999/xhtml">2005-06-18: created</h:div>
            </xsd:documentation>
        </xsd:annotation>
    </xsd:attribute>
</xsd:attributeGroup>