http://hl7.org/fhir/StructureDefinition/structuredefinition-hierarchy|5.2.0
For circular references (references back to the same type of resource): whether they are allowed to transitively point back to the same instance (false), or whether the relationship must be a strict one-way hierarchy (true).
| element_id | types |
|---|---|
| Extension | |
| Extension.extension | |
| Extension.url | |
| Extension.value[x] | |
| Extension | |
| Extension.id | |
| Extension.extension | |
| Extension.url | |
| Extension.value[x] |