Two association classes are introduced in the Entity identification model as shown in Figure EI.08 – Use of an Entity Identification Specification below.  The EntityIdentificationSpecFormat association class, which was first shown in Figure EI.07 – Identifying Entities Using the RootEntityType Entity above, is used to define the formatting and sequencing of EntityIdentificationSpec objects that are aggregated by a particular EntityIdentificationSpecComposite object. The RootEntityTypeIdentificationSpec association class, shown in Figure EI.08 – Use of an Entity Identification Specification below, is used to indicate, via its use attribute, whether the entity identification specification is used as the primary or as a secondary identifier.<br/>