Refined definition of aggregate sequence in Overview of persistence.rst.
@@ -109,11 +109,11 @@ By using a common type for the representation of domain events,
all domain events can be stored and retrieved in a common way.
An **aggregate sequence** is a sequence of stored events for
-an aggregate.
+an aggregate. The originator version number of the event determines
+its position in its sequence.
-An **event notification** is a stored event that also has a 'notification ID'.
-The notification ID identifies the position of an aggregate event in an
-application sequence.
+An **event notification** is a stored event that also has an notification ID.
+The notification ID identifies the position of a the event in this sequence.
An **application sequence** is a sequence of event notifications
for an application.
