In AuditEvent and Provenance the basedOn element references "the workflow authorization ressource within which this event occured".

However, the list of possible ressources does not include the Task ressource.

Since Task can be used a workflow authorization ressource as well (see http://hl7.org/fhir/2021May/workflow.html#list ) we propose to add it to the list of possible references for basedOn.

See also the minutes of the FHIR workflow call:

https://confluence.hl7.org/x/npWfBg