the Namespace of the described/configured Schema. Should include the version of the schema eg http://www.bgbm.org/tdwg/abcd/v1.0 The xpath to the element used as the Identifier for the basic record of the concept. E.g Units for ABCD, or maybe names for other concepts. Important for the count method. An element (inherits attribute properties) A simpleType to represent a URL that does a pattern match to verify a full URL without whitespace. A simpleType to represent an xpath-type used for querying.