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• Occurrence and OccurrenceKind are not clearly distinct. Why is a Transaction event not just a subclass of Occurrence? It fits the definition. 

Payment and Payment Event

• What is the difference - the English definition does not adequately distiguish the meanings of these two. 

Recommended Changes

Definition not match axioms 

• oc:Occurrence definition says there is both a date and a location, but there is no restriction for a date. Should be added.
  "An Occurrence is a happening of an OccurrenceKind. Each Occurrence has a DateTimeStamp, which identifies when the Occurrence happened, and a Location" 

Making things simpler

Contract and ContractTermsSet

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