complexType BaseUnitType

diagram
namespace	http://www.opengis.net/gml
type	extension of gml:UnitDefinitionType
properties	base  gml:UnitDefinitionType
children	gml:metaDataProperty gml:description gml:name gml:quantityType gml:catalogSymbol gml:unitsSystem
used by	element  BaseUnit
attributes	Name   Type   Use   Default   Fixed   annotation id required         documentation Database handle for the object.  It is of XML type ID, so is constrained to be unique in the XML document within which it occurs.  An external identifier for the object in the form of a URI may be constructed using standard XML and XPointer methods.  This is done by concatenating the URI for the document, a fragment separator, and the value of the id attribute.
annotation	documentation Definition of a unit of measure which is a base unit from the system of units.  A base unit cannot be derived by combination of other base units within this system.  Sometimes known as "fundamental unit".
source	<xs:complexType name="BaseUnitType">   <xs:annotation>     <xs:documentation>Definition of a unit of measure which is a base unit from the system of units.  A base unit cannot be derived by combination of other base units within this system.  Sometimes known as "fundamental unit".</xs:documentation>   </xs:annotation>   <xs:complexContent>     <xs:extension base="gml:UnitDefinitionType">       <xs:sequence>         <xs:element name="unitsSystem" type="gml:ReferenceType"/>       </xs:sequence>     </xs:extension>   </xs:complexContent> </xs:complexType>

element BaseUnitType/unitsSystem

diagram
namespace	http://www.opengis.net/gml
type	gml:ReferenceType
properties	isRef  0 content  complex
attributes	Name   Type   Use   Default   Fixed   annotation type       simple   href          role          arcrole          title          show          actuate          remoteSchema optional         documentation Reference to an XML Schema fragment that specifies the content model of the propertys value. This is in conformance with the XML Schema Section 4.14 Referencing Schemas from Elsewhere.
source	<xs:element name="unitsSystem" type="gml:ReferenceType"/>

XML Schema documentation generated by XMLSpy Schema Editor http://www.altova.com/xmlspy