EDOC — Chapter 3, Section 4.2.2.7 "Notification Rule" pg 250 - Related to "Node"

The text says "A NotificationRule governs the entry into or exit from
one Node (or the exit from one and entry into another, i.e. 2 Nodes)"
How is one to dertermine which of these 3 options is to be used? The
multiplicity on the Node end of the governs association is 1..2, so we
can assume that the 3rd option applies when there are 2 links... but
when there is only 1 link, which is it?

Suggested Resolution: Add a new association with roles "governsExit/
exitGovernedBy" with multiplicity 1 at the Node end, and 0..1 at the
NotificationRule end. Change the existing governs/governedBy
association to be "governsEntry/entryGoverenedBy" with multiplicity 1
at the Node end, and 0..1 at the NotificationRule end. The 3rd case
should be modelled as a NotificationRule governing a Transition between
Nodes.