<xsd:group name="面積型-固有要素グループ"> <xsd:sequence> <xsd:element ref="ic:数値" minOccurs="0" maxOccurs="1" /> <xsd:element ref="ic:単位" minOccurs="0" maxOccurs="1" /> <xsd:element ref="ic:単位表記" minOccurs="0" maxOccurs="1" /> </xsd:sequence> </xsd:group>