Restrict the performer Reference datatype to the LiteralReference profile and its target types to Practitioner or PractitionerRole. Note that the first rule restricts the Reference datatype and the second rule restricts the types it can refer to:

• performer only LiteralReference
• performer only Reference(PrimaryCarePhysician or EmergencyRoomPhysician)

Quite confusing. Is LiteralReference something from FSH that restricts the reference to exactly the ones specified and not specialized profiles if any? This keyword???? Is not mentioned anywhere else. What does it mean "restricts the types it can refer to"? Could be that this is just an example name but it could also imply something more fundamental.

We suggest to change the sentence to:

Define a profile on Reference named LiteralReference. Restrict the performer Reference datatype to this LiteralReference profile and its target types to Practitioner or PractitionerRole. Note that the first rule restricts the Reference datatype and the second rule restricts the types it can refer to:

• performer only LiteralReference
• performer only Reference(PrimaryCarePhysician or EmergencyRoomPhysician)