1. Conventions

The following conventions are used in the manual ... (insert details here).

1.1. XML Annotation

XML definitions are annotated with BNF-style markers to indicate alternative (|), multiples (* or +), and optional (?) items. If no annotation is present then the item must be present once.

|
Indicates an alternative option. Only one of the items separated by | is to be chosen.
*
Following an item, * indicates the item may occur any number of times, including no times (0 or more multiple).
+
Following an item, + indicates the item must occur at least once, but may occur more than ones (1 or more multiple).
?
Following an item, ? indicates the item may occur at most once, if present (0 or 1 times).