UML22 — See CommonBehavior for a description of Event specifications

The text says "See CommonBehavior for a description of Event specifications."

Under the heading,Basic Behaviors, on page 370, Section 13 mentions call behavior event, trigger event, start event and termination event; the next page mentions send invocation event, send event, invocation event, call invocation event, signal event, receive event, receiving event; there may be others.

But we aren't told there or anywhere how to specify an event nor how to specify a type of event.

see above THEN below