diff --git a/frontend/src/lib/models/datatypes/identifier-model.ts b/frontend/src/lib/models/datatypes/identifier-model.ts
new file mode 100644
index 00000000..3a79c5b1
--- /dev/null
+++ b/frontend/src/lib/models/datatypes/identifier-model.ts
@@ -0,0 +1,8 @@
+import {CodableConceptModel} from './codable-concept-model';
+
+export interface IdentifierModel {
+  use: string
+  type?: CodableConceptModel
+  system?: string
+  value?: string
+}
diff --git a/frontend/src/lib/models/datatypes/reference-model.ts b/frontend/src/lib/models/datatypes/reference-model.ts
index 1508a41e..86f61133 100644
--- a/frontend/src/lib/models/datatypes/reference-model.ts
+++ b/frontend/src/lib/models/datatypes/reference-model.ts
@@ -1,4 +1,7 @@
+import {IdentifierModel} from './identifier-model';
+
 export interface ReferenceModel {
   reference: string
   display?: string
+  identifier?: IdentifierModel
 }