2.2.6.2.11 Links and Subtypes
Entity instances in an EntitySet MAY not belong to the same EntityType but MUST all be derived from the EntityType baseType associated with the EntitySet. In addition to the rules described in Entity Set (as an Atom Feed Element (section 2.2.6.2.1), the following rules apply:
The edit link for an EntityType, if present, MUST be represented as a link element that SHOULD have an href attribute that includes the namespace qualified EntityType. For example, http://host/service.svc/Customers/ ('ALFKI2')/ SampleModel.VipCustomer
There MAY also be a link element for the entity’s self link. If this element is present, it SHOULD have the href attribute set to the namespace-qualified EntityType. For example,http://host/service.svc/Customers/ ('ALFKI2')/ SampleModel.VipCustomer
If an EntityType has a NavigationProperty, the following rules apply (in addition to those described in Deferred Content (section 2.2.6.2.6)):
The link for the NavigationProperty on the EntityType, if present, MUST be represented as a link element that SHOULD have an href attribute that includes the namespace qualified EntityType on which the NavigationProperty exists. For example,http://host/service.svc/Customers/ ('ALFKI2')/ SampleModel.VipCustomer/InHouseStaff
The association link that describes the relationship between the related entities MUST be represented as a link element that SHOULD have the href attribute that includes the namespace qualified EntityType on which the NavigationProperty exists. For example, http://host/service.svc/Customers/ ('ALFKI2')/ SampleModel.VipCustomer/$links/InHouseStaff
If an EntityType has named resource streams, the following rules apply (in addition to those described in section Named Resource Streams (section 2.2.6.2.10)):
The href attribute of the, media-resource and edit-media links SHOULD include the namespace-qualified EntityType on which the named resource stream exists. For example, http://host/service.svc/Customers/ ('ALFKI2')/ SampleModel.VipCustomer/Logo